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Educational essentialism

Educational essentialism is an educational philosophy whose adherents believe that children should learn the traditional basic subjects thoroughly. In this philosophical school of thought, the aim is to instill students with the "essentials" of academic knowledge, enacting a back-to-basics approach. Essentialism ensures that the accumulated wisdom of our civilization as taught in the traditional academic disciplines is passed on from teacher to student. Such disciplines might include Reading, Writing, Literature, Foreign Languages, History, Mathematics, Classical Languages, Science, Art, and Music. Moreover, this traditional approach is meant to train the mind, promote reasoning, and ensure a common culture.

Principles of essentialism
Essentialism is a relatively conservative stance to education that strives to teach students the knowledge of a society and civilization through a core curriculum. This core curriculum involves such areas that include; the study of the surrounding environment, basic natural laws, and the disciplines that promote a happier, more educated living. Other non-traditional areas are also integrated as well in moderation to balance the education. Essentialists' goals are to instill students with the "essentials" of academic knowledge, patriotism, and character development through traditional (or back-to-basic) approaches. This is to promote reasoning, train the mind, and ensure a common culture for all citizens.

Essentialism is the most typically enacted philosophy in American classrooms today. Traces of this can be found in the organized learning centered on teachers and textbooks, in addition to the regular assignments and evaluations.

Essentialism as a teacher-centered philosophy
The role of the teacher as the leader of the classroom is a very important tenet of Educational essentialism. The teacher is the center of the classroom, so they should be rigid and disciplinary. Establishing order in the classroom is crucial for student learning; effective teaching cannot take place in a loud and disorganized environment. It is the teacher's responsibility to keep order in the classroom. The teacher must interpret essentials of the learning process, take the leadership position and set the tone of the classroom. These needs require an educator who is academically well-qualified with an appreciation for learning and development. The teacher must control the students with distributions of rewards and penalties. It has been argued that recent teacher education policies in some countries extend essentialism to teacher education policy frameworks.

History of essentialism
The Essentialist movement first began in the United States in the year 1938. In Atlantic City, New Jersey, a group met for the first time called "The Essentialist's Committee for the Advancement of Education." Their emphasis was to reform the educational system to a rationality-based system.

The term essentialist first appeared in the book An Introduction to the Philosophy of Education which was written by Michael John Demiashkevich. In his book, Demiashkevich labels some specific educators (including William C. Bagley) as “essentialists." Demiashkevich compared the essentialists to the different viewpoints of the Progressive Education Association. He described how the Progressives preached a “hedonistic doctrine of change” whereas the essentialists stressed the moral responsibility of man for his actions and looked toward permanent principles of behavior (Demiashkevich likened the arguments to those between the Socratics and the Sophists in Greek philosophy). In 1938 Bagley and other educators met together where Bagley gave a speech detailing the main points of the essentialism movement and attacking the public education in the United States. One point that Bagley noted was that students in the U.S. were not getting an education on the same levels as students in Europe who were the same age.

A recent branch has emerged within the essentialist school of thought called "neoessentialism." Emerging in the eighties as a response to the essentialist ideals of the thirties as well as to the criticism of the fifties and the advocates for education in the seventies, neoessentialism was created to try to appease the problems facing the United States at the time. The most notable change within this school of thought is that it called for the creation of a new discipline, computer science.

Renowned essentialists
William Bagley (1874–1946) was an important historical essentialist. William C. Bagley completed his undergraduate degree at Michigan Agricultural College in 1895. It wasn't until after finishing his undergraduate studies that he truly wanted to be a teacher. Bagley did his Graduate studies at the University of Chicago and at Cornell University. He acquired his Ph.D. in 1900, after which he took his first school job as a Principal in a St. Louis, Missouri Elementary School. Bagley's devotion increased during his work at Montana State Normal School in Dillon, Montana. It was here where he decided to dedicate his time to the education of teachers and where he published The Educative Process, launching his name across the nation. Throughout his career Bagley argued against the conservative position that teachers were not in need of special training for their work. He believed that liberal arts material was important in teacher education. Bagley also believed the dominant theories of education of the time were weak and lacking.

In April 1938, he published the Essentialist's Platform, in which he outlined three major points of essentialism. He described the right of students to a well-educated and culturally knowledgeable teacher. Secondly, he discussed the importance of teaching the ideals of community to each group of students. Lastly, Bagley wrote of the importance of accuracy, thoroughness and effort on the part of the student in the classroom.

Another important essentialist is E. D. Hirsch (1928-). Hirsch was Founder and Chairman of the Core Knowledge Foundation and authored several books concerning fact-based approaches to education. Now retired, he spent many years teaching at the University of Virginia while also being an advocate for the "back to basics" movement. In his most popular book, Cultural Literacy — What Every American Needs To Know, he offers lists, quotations, and information regarding what he believes is essential knowledge.

See also Arthur Bestor.

Schools enacting an essentialist curriculum
The Core Knowledge Schools were founded on the philosophy of essentialist E.D. Hirsch. Although it is difficult to maintain a pure and strict essentialist-only curriculum, these schools have the central aim of establishing a common knowledge base for all citizens. To do so, they follow a nationwide, content-specific, and teacher-centered curriculum. The Core Knowledge curriculum also allows for local variance above and beyond the core curriculum. Central curricular aims are academic excellence and the learning of knowledge, and teachers who are masters of their knowledge areas serve this aim.

Criticism of essentialism
Because Essentialism is largely teacher-centered, the role of the student is often called into question. Presumably, in an essentialist classroom, the teacher is the one designing the curriculum for the students based upon the core disciplines. Moreover, he or she is enacting the curriculum and setting the standards which the students must meet. The teacher's evaluative role may undermine students' interest in study. As a result, the students begin to take on more of a passive role in their education as they are forced to meet and learn such standards and information.

Furthermore, there is also speculation that an essentialist education helps in promoting the cultural lag. This philosophy of education is very traditional in the mindset of passing on the knowledge of the culture via the academic disciplines. Thus, students are forced to think in the mindset of the larger culture, and individual creativity, and subversive investigation are often not emphasized, or even outright discouraged.

title: Educational essentialism


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Progressive education

Progressive education, or educational progressivism, is a pedagogical movement that began in the late 19th century and has persisted in various forms to the present. In Europe, progressive education took the form of the New Education Movement. The term progressive was engaged to distinguish this education from the traditional curricula of the 19th century, which was rooted in classical preparation for the early-industrial university and strongly differentiated by social class. By contrast, progressive education finds its roots in modern, post-industrial experience. Most progressive education programs have these qualities in common:

 * Emphasis on learning by doing – hands-on projects, expeditionary learning, experiential learning
 * Integrated curriculum focused on thematic units
 * Strong emphasis on problem solving and critical thinking
 * Group work and development of social skills
 * Understanding and action as the goals of learning as opposed to rote knowledge
 * Collaborative and cooperative learning projects
 * Education for social responsibility and democracy
 * Integration of community service and service learning projects into the daily curriculum
 * Selection of subject content by looking forward to ask what skills will be needed in future society
 * De-emphasis on textbooks in favor of varied learning resources
 * Emphasis on lifelong learning and social skills
 * Assessment by evaluation of child's projects and productions

History
Progressive education can be traced back to the works of John Locke and Jean-Jacques Rousseau, both of whom are known as forerunners of ideas that would be developed by theorists such as John Dewey. Considered one of the first of the British empiricists, Locke believed that "truth and knowledge… arise out of observation and experience rather than manipulation of accepted or given ideas". He further discussed the need for children to have concrete experiences in order to learn. Rousseau deepened this line of thinking in Emile, or On Education, where he argued that subordination of students to teachers and memorization of facts would not lead to an education.

Johann Bernhard Basedow
In Germany, Johann Bernhard Basedow (1724–1790) established the Philanthropinum at Dessau in 1774. He developed new teaching methods based on conversation and play with the child, and a program of physical development. Such was his success that he wrote a treatise on his methods, "On the best and hitherto unknown method of teaching children of noblemen".

Christian Gotthilf Salzmann
Christian Gotthilf Salzmann (1744–1811) was the founder of the Schnepfenthal institution, a school dedicated to new modes of education (derived heavily from the ideas of Jean-Jacques Rousseau). He wrote Elements of Morality, for the Use of Children, one of the first books translated into English by Mary Wollstonecraft.

Johann Heinrich Pestalozzi
Johann Heinrich Pestalozzi (1746–1827) was a Swiss pedagogue and educational reformer who exemplified Romanticism in his approach. He founded several educational institutions both in German- and French-speaking regions of Switzerland and wrote many works explaining his revolutionary modern principles of education. His motto was "Learning by head, hand and heart". His research and theories closely resemble those outlined by Rousseau in Emile. He is further considered by many to be the "father of modern educational science" His psychological theories pertain to education as they focus on the development of object teaching, that is, he felt that individuals best learned through experiences and through a direct manipulation and experience of objects. He further speculated that children learn through their own internal motivation rather than through compulsion. (See Intrinsic vs. Extrinsic motivation). A teacher's task will be to help guide their students as individuals through their learning and allow it to unfold naturally.

Friedrich Fröbel
Friedrich Wilhelm August Fröbel (1782–1852) was a student of Pestalozzi who laid the foundation for modern education based on the recognition that children have unique needs and capabilities. He believed in "self-activity" and play as essential factors in child education. The teacher's role was not to indoctrinate but to encourage self-expression through play, both individually and in group activities. He created the concept of kindergarten.

Johann Friedrich Herbart
Johann Friedrich Herbart (1776–1841) emphasized the connection between individual development and the resulting societal contribution. The five key ideas which composed his concept of individual maturation were Inner Freedom, Perfection, Benevolence, Justice, and Equity or Recompense. According to Herbart, abilities were not innate but could be instilled, so a thorough education could provide the framework for moral and intellectual development. In order to develop a child to lead to a consciousness of social responsibility, Herbart advocated that teachers utilize a methodology with five formal steps: "Using this structure a teacher prepared a topic of interest to the children, presented that topic, and questioned them inductively, so that they reached new knowledge based on what they had already known, looked back, and deductively summed up the lesson's achievements, then related them to moral precepts for daily living".

John Melchior Bosco
John Melchior Bosco (1815–1888) was concerned about the education of street children who had left their villages to find work in the rapidly industrialized city of Turin, Italy. Exploited as cheap labor or imprisoned for unruly behavior, Bosco saw the need for creating a space where they would feel at home. He called it an 'Oratory' where they could play, learn, share friendships, express themselves, develop their creative talents and pick up skills for gainful self-employment. With those who had found work, he set up a mutual-fund society (an early version of the Grameen Bank) to teach them the benefits of saving and self-reliance. The principles underlying his educational method that won over the hearts and minds of thousands of youth who flocked to his oratory were: 'be reasonable', 'be kind', 'believe' and 'be generous in service'. Today his method of education is practiced in nearly 3000 institutions set up around the world by the members of the Salesian Society he founded in 1873.

Cecil Reddie
While studying for his doctorate in Göttingen in 1882–1883, Cecil Reddie was greatly impressed by the progressive educational theories being applied there. Reddie founded Abbotsholme School in Derbyshire, England, in 1889. Its curriculum enacted the ideas of progressive education. Reddie rejected rote learning, classical languages and corporal punishment. He combined studies in modern languages and the sciences and arts with a program of physical exercise, manual labour, recreation, crafts and arts. Schools modeling themselves after Abbotsholme were established throughout Europe, and the model was particularly influential in Germany. Reddie often engaged foreign teachers, who learned its practices, before returning home to start their own schools. Hermann Lietz an Abbotsholme teacher founded five schools (Landerziehungsheime für Jungen) on Abbotsholme's principles. Other people he influenced included Kurt Hahn, Adolphe Ferrière and Edmond Demolins. His ideas also reached Japan, where it turned into "Taisho-era Free Education Movement" (Taisho Jiyu Kyoiku Undo)

John Dewey
Education according to John Dewey is the "participation of the individual in the social consciousness of the race" (Dewey, 1897, para. 1). As such, education should take into account that the student is a social being. The process begins at birth with the child unconsciously gaining knowledge and gradually developing their knowledge to share and partake in society.

For Dewey, education, which regulates "the process of coming to share in the social consciousness," is the "only sure" method of ensuring social progress and reform (Dewey, 1897, para. 60). In this respect, Dewey foreshadows Social Reconstructionism, whereby schools are a means to reconstruct society. As schools become a means for social reconstruction, they must be given the proper equipment to perform this task and guide their students.

Helen Parkhurst
The American teacher Helen Parkhurst (1886–1973) developed the Dalton Plan at the beginning of the twentieth century with the goal of reforming the then current pedagogy and classroom management. She wanted to break the teacher-centered lockstep teaching. During her first experiment, which she implemented in a small elementary school as a young teacher in 1904, she noticed that when students are given freedom for self-direction and self-pacing and to help one another, their motivation increases considerably and they learn more. In a later experiment in 1911 and 1912, Parkhurst re-organized the education in a large school for nine- to fourteen-year-olds. Instead of each grade, each subject was appointed its own teacher and its own classroom. The subject teachers made assignments: they converted the subject matter for each grade into learning assignments. In this way, learning became the students' own work; they could carry out their work independently, work at their own pace and plan their work themselves. The classroom turned into a laboratory, a place where students are working, furnished and equipped as work spaces, tailored to meet the requirements of specific subjects. Useful and attractive learning materials, instruments and reference books were put within the students' reach. The benches were replaced by large tables to facilitate co-operation and group instruction. This second experiment formed the basis for the next experiments, those in Dalton and New York, from 1919 onwards. The only addition was the use of graphs, charts enabling students to keep track of their own progress in each subject.

In the nineteen-twenties and nineteen-thirties, Dalton education spread throughout the world. There is no certainty regarding the exact numbers of Dalton schools, but there was Dalton education in America, Australia, England, Germany, the Netherlands, the Soviet Union, India, China and Japan.

Rudolf Steiner
Rudolf Steiner (1861–1925) first described the principles of what was to become Waldorf education in 1907. He established a series of schools based on these principles beginning in 1919. The focus of the education is on creating a developmentally appropriate curriculum that holistically integrates practical, artistic, social, and academic experiences. There are more than a thousand schools and many more early childhood centers worldwide; it has also become a popular form of homeschooling.

Maria Montessori
Maria Montessori (1870–1952) began to develop her philosophy and methods in 1897. She based her work on her observations of children and experimentation with the environment, materials, and lessons available to them. She frequently referred to her work as "scientific pedagogy", arguing for the need to go beyond observation and measurement of students, to developing new methods to transform them. Although Montessori education spread to the United States in 1911 there were conflicts with the American educational establishment and was opposed by William Heard Kilpatrick. However Montessori education returned to the United States in 1960 and has since spread to thousands of schools there.

In 1914 the Montessori Society in England organised its first conference. Hosted by Rev Bertram Hawker, who had set up, in partnership with his local elementary school in the Norfolk coastal village of East Runton, the first Montessori School in England. Pictures of this school, and its children, illustrated the 'Montessori's Own Handbook' (1914). Hawker had been impressed by his visit to Montessori's Casa dei Bambini in Rome, he gave numerous talks on Montessori's work after 1912, assisting in generating a national interest in her work. He organised the Montessori Conference 1914 in partnership with Edmond Holmes, ex-Chief Inspector of Schools, who had written a government report on Montessori. The conference decided that its remit was to promote the 'liberation of the child in the school', and though inspired by Montessori, would encourage, support and network teachers and educationalists who sought, through their schools and methods, that aim. They changed their name the following year to New Ideals in Education. Each subsequent conference was opened with reference to its history and origin as a Montessori Conference recognising her inspiration, reports italicized the members of the Montessori Society in the delegate lists, and numerous further events included Montessori methods and case studies. Montessori, through New Ideals in Education, its committee and members, events and publications, greatly influenced progressive state education in England. (references to be added).

Robert Baden-Powell
In July 1906, Ernest Thompson Seton sent Robert Baden-Powell a copy of his book The Birchbark Roll of the Woodcraft Indians. Seton was a British-born Canadian-American living in the United States. They shared ideas about youth training programs. In 1907 Baden-Powell wrote a draft called Boy Patrols. In the same year, to test his ideas, he gathered 21 boys of mixed social backgrounds and held a week-long camp in August on Brownsea Island in England. His organizational method, now known as the Patrol System and a key part of Scouting training, allowed the boys to organize themselves into small groups with an elected patrol leader. Baden Powell then wrote Scouting for Boys (London, 1908). The Brownsea camp and the publication of Scouting for Boys are generally regarded as the start of the Scout movement which spread throughout the world. Baden-Powell and his sister Agnes Baden-Powell introduced the Girl Guides in 1910.

Comparison with traditional education
Traditional education uses extrinsic motivation, such as grades and prizes. Progressive education is more likely to use intrinsic motivation, basing activities on the interests of the child. Praise may be discouraged as a motivator. Progressive education is a response to traditional methods of teaching. It is defined as an educational movement which gives more value to experience than formal learning. It is based more on experiential learning that concentrate on the development of a child's talents.

21st century skills
21st century skills are a series of higher-order skills, abilities, and learning dispositions that have been identified as being required for success in the rapidly changing, digital society and workplaces. Many of these skills are also defining qualities of progressive education as well as being associated with deeper learning, which is based on mastering skills such as analytic reasoning, complex problem solving, and teamwork. These skills differ from traditional academic skills in that they are not primarily content knowledge-based.

Germany
Hermann Lietz founded three Landerziehungsheime (country boarding schools) in 1904 based on Reddie's model for boys of different ages. Lietz eventually succeeded in establishing five more Landerziehungsheime. Edith and Paul Geheeb founded Odenwaldschule in Heppenheim in the Odenwald in 1910 using their concept of progressive education, which integrated the work of the head and hand.

Poland
Janusz Korczak was one notable follower and developer of  Pestalozzi's ideas. He wrote ''The names of Pestalozzi, Froebel and Spencer shine with no less brilliance than the names of the greatest inventors of the twentieth century. For they discovered more than the unknown forces of nature; they discovered the unknown half of humanity: children.'' His Orphan's Home in Warsaw became a model institution and exerted influence on the educational process in other orphanages of the same type.

Ireland
The Quaker school run in Ballitore, Co Kildare in the 18th century had students from as far away as Bordeaux (where there was a substantial Irish émigré population), the Caribbean and Norway. Notable pupils included Edmund Burke and Napper Tandy. Sgoil Éanna, or in English St Enda's was founded in 1908 by Pádraig Pearse on Montessori principles. Its former assistant headmaster Thomas MacDonagh and other teachers including Pearse; games master Con Colbert; Pearse's brother, Willie, the art teacher, and Joseph Plunkett, and occasional lecturer in English, were executed by the British after the 1916 Rising. Pearse and MacDonagh were two of the seven leaders who signed the Irish Declaration of Independence. Pearse's book The Murder Machine was a denunciation of the English school system of the time and a declaration of his own educational principles.

Sweden
In Sweden, an early proponent of progressive education was Alva Myrdal, who with her husband Gunnar co-wrote Kris i befolkningsfrågan (1934), a most influential program for the social-democratic hegemony (1932–1976) popularly known as "Folkhemmet". School reforms went through government reports in the 1940s and trials in the 1950s, resulting in the introduction in 1962 of public comprehensive schools ("grundskola") instead of the previously separated parallel schools for theoretical and non-theoretical education.

United Kingdom
The ideas from Reddie's Abbotsholme spread to schools such as Bedales School (1893), King Alfred School, London (1898) and St Christopher School, Letchworth (1915), as well as all the Friends' schools, Steiner Waldorf schools and those belonging to the Round Square Conference. The King Alfred School was radical for its time in that it provided a secular education and that boys and girls were educated together. Alexander Sutherland Neill believed children should achieve self-determination and should be encouraged to think critically rather than blindly obeying. He implemented his ideas with the founding of Summerhill School in 1921. Neill believed that children learn better when they are not compelled to attend lessons. The school was also managed democratically, with regular meetings to determine school rules. Pupils had equal voting rights with school staff.

Early practitioners
Fröbel's student Margarethe Schurz founded the first kindergarten in the United States at Watertown, Wisconsin, in 1856, and she also inspired Elizabeth Peabody, who went on to found the first English-speaking kindergarten in the United States – the language at Schurz's kindergarten had been German, to serve an immigrant community – in Boston in 1860. This paved the way for the concept's spread in the USA. The German émigré Adolph Douai had also founded a kindergarten in Boston in 1859, but was obliged to close it after only a year. By 1866, however, he was founding others in New York City.

William Heard Kilpatrick (1871–1965) was a pupil of Dewey and one of the most effective practitioners of the concept as well as the more adept at proliferating the progressive education movement and spreading word of the works of Dewey. He is especially well known for his "project method of teaching". This developed the progressive education notion that students were to be engaged and taught so that their knowledge may be directed to society for a socially useful need. Like Dewey he also felt that students should be actively engaged in their learning rather than actively disengaged with the simple reading and regurgitation of material.

The most famous early practitioner of progressive education was Francis Parker; its best-known spokesperson was the philosopher John Dewey. In 1875 Francis Parker became superintendent of schools in Quincy, Massachusetts, after spending two years in Germany studying emerging educational trends on the continent. Parker was opposed to rote learning, believing that there was no value in knowledge without understanding. He argued instead schools should encourage and respect the child's creativity. Parker's Quincy System called for child-centered and experience-based learning. He replaced the traditional curriculum with integrated learning units based on core themes related to the knowledge of different disciplines. He replaced traditional readers, spellers and grammar books with children's own writing, literature, and teacher prepared materials. In 1883 Parker left Massachusetts to become Principal of the Cook County Normal School in Chicago, a school that also served to train teachers in Parker's methods. In 1894 Parker's Talks on Pedagogics, which drew heavily on the thinking of Fröbel, Pestalozzi and Herbart, became one of the first American writings on education to gain international fame.

That same year, philosopher John Dewey moved from the University of Michigan to the newly established University of Chicago where he became chair of the department of philosophy, psychology and education. He and his wife enrolled their children in Parker's school before founding their own school two years later.

Whereas Parker started with practice and then moved to theory, Dewey began with hypotheses and then devised methods and curricula to test them. By the time Dewey moved to Chicago at the age of thirty-five, he had already published two books on psychology and applied psychology. He had become dissatisfied with philosophy as pure speculation and was seeking ways to make philosophy directly relevant to practical issues. Moving away from an early interest in Hegel, Dewey proceeded to reject all forms of dualism and dichotomy in favor of a philosophy of experience as a series of unified wholes in which everything can be ultimately related.

In 1896, John Dewey opened what he called the laboratory school to test his theories and their sociological implications. With Dewey as the director and his wife as principal, the University of Chicago Laboratory school, was dedicated "to discover in administration, selection of subject-matter, methods of learning, teaching, and discipline, how a school could become a cooperative community while developing in individuals their own capacities and satisfy their own needs." (Cremin, 136) For Dewey the two key goals of developing a cooperative community and developing individuals' own capacities were not at odds; they were necessary to each other. This unity of purpose lies at the heart of the progressive education philosophy. In 1912, Dewey sent out students of his philosophy to found The Park School of Buffalo and The Park School of Baltimore to put it into practice. These schools operate to this day within a similar progressive approach.

At Columbia, Dewey worked with other educators such as Charles Eliot and Abraham Flexner to help bring progressivism into the mainstream of American education. In 1917 Columbia established the Lincoln School of Teachers College "as a laboratory for the working out of an elementary and secondary curriculum which shall eliminate obsolete material and endeavor to work up in usable form material adapted to the needs of modern living." (Cremin, 282) Based on Flexner's demand that the modern curriculum "include nothing for which an affirmative case can not be made out" (Cremin, 281) the new school organized its activities around four fundamental fields: science, industry, aesthetics and civics. The Lincoln School built its curriculum around "units of work" that reorganized traditional subject matter into forms embracing the development of children and the changing needs of adult life. The first and second grades carried on a study of community life in which they actually built a city. A third grade project growing out of the day-to-day life of the nearby Hudson River became one of the most celebrated units of the school, a unit on boats, which under the guidance of its legendary teacher Miss Curtis, became an entrée into history, geography, reading, writing, arithmetic, science, art and literature. Each of the units was broadly enough conceived so that different children could concentrate on different aspects depending on their own interests and needs. Each of the units called for widely diverse student activities, and each sought to deal in depth with some critical aspect of contemporary civilization. Finally each unit engaged children working together cooperatively and also provided opportunities for individual research and exploration.

In 1924, Agnes de Lima, the lead writer on education for The New Republic and The Nation, published a collection of her articles on progressive education as a book, titled Our Enemy the Child.

In 1918, the National Education Association, representing superintendents and administrators in smaller districts across the country, issued its report "Cardinal Principles of Secondary Education." It emphasized the education of students in terms of health, a command of fundamental processes, worthy home membership, vocation, citizenship, worthy use of leisure, and ethical character. They emphasized life adjustment and reflected the social efficiency model of progressive education.

From 1919 to 1955, the Progressive Education Association founded by Stanwood Cobb and others worked to promote a more student-centered approach to education. During the Great Depression the organization conducted the Eight-Year Study, evaluating the effects of progressive programs. More than 1500 students over four years were compared to an equal number of carefully matched students at conventional schools. When they reached college, the experimental students were found to equal or surpass traditionally educated students on all outcomes: grades, extracurricular participation, dropout rates, intellectual curiosity, and resourcefulness. Moreover, the study found that the more the school departed from the traditional college preparatory program, the better was the record of the graduates. (Kohn, Schools, 232)

By mid-century, many public school programs had also adopted elements of progressive curriculum. At mid-century Dewey believed that progressive education had "not really penetrated and permeated the foundations of the educational institution."(Kohn, Schools, 6,7) As the influence of progressive pedagogy grew broader and more diffuse, practitioners began to vary their application of progressive principles. As varying interpretations and practices made evaluation of progressive reforms more difficult to assess, critics began to propose alternative approaches.

The seeds of the debate over progressive education can be seen in the differences of Parker and Dewey. These have to do with how much and by whom curriculum should be worked out from grade to grade, how much the child's emerging interests should determine classroom activities, the importance of child-centered vs. societal–centered learning, the relationship of community building to individual growth, and especially the relationship between emotion, thought and experience.

In 1955, the publication of Rudolf Flesch's Why Johnny Can't Read leveled criticism of reading programs at the progressive emphasis on reading in context. The conservative McCarthy era raised questions about the liberal ideas at the roots of the progressive reforms. The launching of Sputnik in 1957 at the height of the Cold War gave rise to a number of intellectually competitive approaches to disciplinary knowledge, such as BSCS biology PSSC physics, led by university professors such as Jerome Bruner and Jerrold Zacharias.

Some Cold War reforms incorporated elements of progressivism. For example, the work of Zacharias and Bruner was based in the developmental psychology of Jean Piaget and incorporated many of Dewey's ideas of experiential education. Bruner's analysis of developmental psychology became the core of a pedagogical movement known as constructivism, which argues that the child is an active participant in making meaning and must be engaged in the progress of education for learning to be effective. This psychological approach has deep connections to the work of both Parker and Dewey and led to a resurgence of their ideas in second half of the century.

In 1965, President Johnson inaugurated the Great Society and the Elementary and Secondary Education Act suffused public school programs with funds for sweeping education reforms. At the same time the influx of federal funding also gave rise to demands for accountability and the behavioral objectives approach of Robert F. Mager and others foreshadowed the No Child Left Behind Act passed in 2002. Against these critics eloquent spokespersons stepped forward in defense of the progressive tradition. The Open Classroom movement, led by Herb Kohl and George Dennison, recalled many of Parker's child centered reforms.

The late 1960s and early 1970s saw a rise and decline in the number of progressive schools. There were several reasons for the decline:

 * Demographics: As the baby boom passed, traditional classrooms were no longer as over-enrolled, reducing demand for alternatives.
 * The economy: The oil crisis and recession made shoestring schools less viable.
 * Times changed: With the ending of the Vietnam War, social activism waned.
 * Co-optation: Many schools were co-opted by people who didn't believe in the original mission.
 * Centralization: The ongoing centralization of school districts
 * Non-implementation: Schools failed to implement a model of shared governance
 * Interpersonal dynamics: Disagreement over school goals, poor group process skills, lack of critical dialogue, and fear of assertive leadership

Progressive education has been viewed as an alternative to the test-oriented instruction legislated by the No Child Left Behind educational funding act. Alfie Kohn has been an outspoken critic of the No Child Left Behind Act and a passionate defender of the progressive tradition.

India
Rabindranath Tagore (1861–1941) was one of the most effective practitioners of the concept of progressive education. He expanded Santiniketan, which is a small town near Bolpur in the Birbhum district of West Bengal, India, approximately 160 km north of Kolkata. He de-emphasized textbook learning in favor of varied learning resources from nature. The emphasis here was on self-motivation rather than on discipline, and on fostering intellectual curiosity rather than competitive excellence. There were courses on a great variety of cultures, and study programs devoted to China, Japan, and the Middle East. He was of the view that education should be a "joyous exercise of our inventive and constructive energies that help us to build up character."

Japan
Seikatsu Tsuzurikata is a grassroots movement in Japan that has many parallels to the progressive education movement, but it developed completely independently, beginning in the late 1920s. The Japanese progressive educational movement was one of the stepping stones to the modernization of Japan and it has resonated down to the present.

International

 * Blossing, Ulf, Gunn Imsen, and Lejf Moos. "Progressive Education and New Governance in Denmark, Norway, and Sweden." The Nordic Education Model (Springer Netherlands, 2014) pp 133–154.
 * Christou, Theodore Michael. Progressive Education: Revisioning and Reframing Ontario's Public Schools, 1919–1942 (2013)
 * Hughes, John Patrick. "Theory into practice in Australian progressive education: the Enmore Activity School." History of Education Review 44#1 (2015).
 * Keskin, Yusuf. "Progressive Education in Turkey: Reports of John Dewey and his Successors." International Journal of Progressive Education 10#3 (2014).
 * Knoll, Michael. "The Project Method – Its Origin and International Influence". In: Progressive Education Across the Continents. A Handbook, ed. Hermann Röhrs and Volker Lenhart. New York: Lang 1995. pp. 307–318.
 * Knoll, Michael. "The Project Method – Its Origin and International Influence". In: Progressive Education Across the Continents. A Handbook, ed. Hermann Röhrs and Volker Lenhart. New York: Lang 1995. pp. 307–318.

Historiography

 * Graham, Patricia Albjerg. Progressive Education from Arcady to Academe: A History of the Progressive Education Association, 1919–1955 (1967)
 * Reese, William J. "The origins of progressive education." History of Education Quarterly 41#1 (2001): 1-24.
 * Wraga, William G. "Condescension and critical sympathy: Historians of education on progressive education in the United States and England." Paedagogica Historica 50#1-2 (2014): 59-75.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Progressive education


text:
Electronic musical instrument

An electronic musical instrument or electrophone is a musical instrument that produces sound using electronic circuitry. Such an instrument sounds by outputting an electrical, electronic or digital audio signal that ultimately is plugged into a power amplifier which drives a loudspeaker, creating the sound heard by the performer and listener.

An electronic instrument might include a user interface for controlling its sound, often by adjusting the pitch, frequency, or duration of each note. A common user interface is the musical keyboard, which functions similarly to the keyboard on an acoustic piano where the keys are each linked mechanically to swinging string hammers - whereas with an electronic keyboard, the keyboard interface is linked to a synth module, computer or other electronic or digital sound generator, which then creates a sound. However, it is increasingly common to separate user interface and sound-generating functions into a music controller (input device) and a music synthesizer, respectively, with the two devices communicating through a musical performance description language such as MIDI or Open Sound Control. The solid state nature of electronic keyboards also offers differing "feel" and "response", offering a novel experience in playing relative to operating a mechanically linked piano keyboard.

All electronic musical instruments can be viewed as a subset of audio signal processing applications. Simple electronic musical instruments are sometimes called sound effects; the border between sound effects and actual musical instruments is often unclear.

In the 21st century, electronic musical instruments are now widely used in most styles of music. In popular music styles such as electronic dance music, almost all of the instrument sounds used in recordings are electronic instruments (e.g., bass synth, synthesizer, drum machine). Development of new electronic musical instruments, controllers, and synthesizers continues to be a highly active and interdisciplinary field of research. Specialized conferences, such as the International Conference on New Interfaces for Musical Expression, have organized to report cutting-edge work, as well as to provide a showcase for artists who perform or create music with new electronic music instruments, controllers, and synthesizers.

Classification
In musicology, electronic musical instruments are known as electrophones. Electrophones are the fifth category of musical instrument under the Hornbostel-Sachs system. Musicologists typically only classify music as electrophones if the sound is initially produced by electricity, excluding electronically controlled acoustic instruments such as pipe organs and amplified instruments such as electric guitars.

The category was added to the Hornbostel-Sachs musical instrument classification system by Sachs in 1940, in his 1940 book The History of Musical Instruments; the original 1914 version of the system did not include it. Sachs divided electrophones into three subcategories:

 * 51=electrically actuated acoustic instruments (e.g., pipe organ with electronic tracker action)
 * 52=electrically amplified acoustic instruments (e.g., acoustic guitar with pickup)
 * 53=instruments which make sound primarily by way of electrically driven oscillators

The last category included instruments such as theremins or synthesizers, which he called radioelectric instruments.

Francis William Galpin provided such a group in his own classification system, which is closer to Mahillon than Sachs-Hornbostel. For example, in Galpin's 1937 book A Textbook of European Musical Instruments, he lists electrophones with three second-level divisions for sound generation ("by oscillation", "electro-magnetic", and "electro-static"), as well as third-level and fourth-level categories based on the control method.

Present-day ethnomusicologists, such as Margaret Kartomi and Terry Ellingson, suggest that, in keeping with the spirit of the original Hornbostel Sachs classification scheme, if one categorizes instruments by what first produces the initial sound in the instrument, that only subcategory 53 should remain in the electrophones category. Thus, it has been more recently proposed, for example, that the pipe organ (even if it uses electric key action to control solenoid valves) remain in the aerophones category, and that the electric guitar remain in the chordophones category, and so on.

Early examples
In the 18th-century, musicians and composers adapted a number of acoustic instruments to exploit the novelty of electricity. Thus, in the broadest sense, the first electrified musical instrument was the Denis d'or keyboard, dating from 1753, followed shortly by the clavecin électrique by the Frenchman Jean-Baptiste de Laborde in 1761. The Denis d'or consisted of a keyboard instrument of over 700 strings, electrified temporarily to enhance sonic qualities. The clavecin électrique was a keyboard instrument with plectra (picks) activated electrically. However, neither instrument used electricity as a sound source.

The first electric synthesizer was invented in 1876 by Elisha Gray. The "Musical Telegraph" was a chance by-product of his telephone technology when Gray discovered that he could control sound from a self-vibrating electromagnetic circuit and so invented a basic oscillator. The Musical Telegraph used steel reeds oscillated by electromagnets and transmitted over a telephone line. Gray also built a simple loudspeaker device into later models, which consisted of a diaphragm vibrating in a magnetic field.

A significant invention, which later had a profound effect on electronic music, was the audion in 1906. This was the first thermionic valve, or vacuum tube and which led to the generation and amplification of electrical signals, radio broadcasting, and electronic computation, among other things. Other early synthesizers included the Telharmonium (1897), the Theremin (1919), Jörg Mager's Spharophon (1924) and Partiturophone, Taubmann's similar Electronde (1933), Maurice Martenot's ondes Martenot ("Martenot waves", 1928), Trautwein's Trautonium (1930). The Mellertion (1933) used a non-standard scale, Bertrand's Dynaphone could produce octaves and perfect fifths, while the Emicon was an American, keyboard-controlled instrument constructed in 1930 and the German Hellertion combined four instruments to produce chords. Three Russian instruments also appeared, Oubouhof's Croix Sonore (1934), Ivor Darreg's microtonal 'Electronic Keyboard Oboe' (1937) and the ANS synthesizer, constructed by the Russian scientist Evgeny Murzin from 1937 to 1958. Only two models of this latter were built and the only surviving example is currently stored at the Lomonosov University in Moscow. It has been used in many Russian movies—like Solaris—to produce unusual, "cosmic" sounds.

Hugh Le Caine, John Hanert, Raymond Scott, composer Percy Grainger (with Burnett Cross), and others built a variety of automated electronic-music controllers during the late 1940s and 1950s. In 1959 Daphne Oram produced a novel method of synthesis, her "Oramics" technique, driven by drawings on a 35 mm film strip; it was used for a number of years at the BBC Radiophonic Workshop. This workshop was also responsible for the theme to the TV series Doctor Who a piece, largely created by Delia Derbyshire, that more than any other ensured the popularity of electronic music in the UK.

Telharmonium

In 1897 Thaddeus Cahill patented an instrument called the Telharmonium (or Teleharmonium, also known as the Dynamaphone). Using tonewheels to generate musical sounds as electrical signals by additive synthesis, it was capable of producing any combination of notes and overtones, at any dynamic level. This technology was later used to design the Hammond organ. Between 1901 and 1910 Cahill had three progressively larger and more complex versions made, the first weighing seven tons, the last in excess of 200 tons. Portability was managed only by rail and with the use of thirty boxcars. By 1912, public interest had waned, and Cahill's enterprise was bankrupt.

Theremin
Another development, which aroused the interest of many composers, occurred in 1919–1920. In Leningrad, Leon Theremin built and demonstrated his Etherophone, which was later renamed the Theremin. This led to the first compositions for electronic instruments, as opposed to noisemakers and re-purposed machines. The Theremin was notable for being the first musical instrument played without touching it. In 1929, Joseph Schillinger composed First Airphonic Suite for Theremin and Orchestra, premièred with the Cleveland Orchestra with Leon Theremin as soloist. The next year Henry Cowell commissioned Theremin to create the first electronic rhythm machine, called the Rhythmicon. Cowell wrote some compositions for it, which he and Schillinger premiered in 1932.

Ondes Martenot

The ondes Martenot is played with a keyboard or by moving a ring along a wire, creating "wavering" sounds similar to a theremin. It was invented in 1928 by the French cellist Maurice Martenot, who was inspired by the accidental overlaps of tones between military radio oscillators, and wanted to create an instrument with the expressiveness of the cello.

The French composer Olivier Messiaen used the ondes Martenot in pieces such as his 1949 symphony Turangalîla-Symphonie, and his sister-in-law Jeanne Loriod was a celebrated player. It appears in numerous film and television soundtracks, particularly science fiction and horror films. Contemporary users of the ondes Martenot include Tom Waits, Daft Punk and the Radiohead guitarist Jonny Greenwood.

Trautonium

The Trautonium was invented in 1928. It was based on the subharmonic scale, and the resulting sounds were often used to emulate bell or gong sounds, as in the 1950s Bayreuth productions of Parsifal. In 1942, Richard Strauss used it for the bell- and gong-part in the Dresden première of his Japanese Festival Music. This new class of instruments, microtonal by nature, was only adopted slowly by composers at first, but by the early 1930s there was a burst of new works incorporating these and other electronic instruments.

Hammond organ and Novachord

In 1929 Laurens Hammond established his company for the manufacture of electronic instruments. He went on to produce the Hammond organ, which was based on the principles of the Telharmonium, along with other developments including early reverberation units. The Hammond organ is an electromechanical instrument, as it used both mechanical elements and electronic parts. A Hammond organ used spinning metal tonewheels to produce different sounds. A magnetic pickup similar in design to the pickups in an electric guitar is used to transmit the pitches in the tonewheels to an amplifier and speaker enclosure. While the Hammond organ was designed to be a lower-cost alternative to a pipe organ for church music, musicians soon discovered that the Hammond was an excellent instrument for blues and jazz; indeed, an entire genre of music developed built around this instrument, known as the organ trio (typically Hammond organ, drums, and a third instrument, either saxophone or guitar).

The first commercially manufactured synthesizer was the Novachord, built by the Hammond Organ Company from 1938 to 1942, which offered 72-note polyphony using 12 oscillators driving monostable-based divide-down circuits, basic envelope control and resonant low-pass filters. The instrument featured 163 vacuum tubes and weighed 500 pounds. The instrument's use of envelope control is significant, since this is perhaps the most significant distinction between the modern synthesizer and other electronic instruments.

Analogue synthesis 1950–1980
The most commonly used electronic instruments are synthesizers, so-called because they artificially generate sound using a variety of techniques. All early circuit-based synthesis involved the use of analogue circuitry, particularly voltage controlled amplifiers, oscillators and filters. An important technological development was the invention of the Clavivox synthesizer in 1956 by Raymond Scott with subassembly by Robert Moog. French composer and engineer Edgard Varèse created a variety of compositions using electronic horns, whistles, and tape. Most notably, he wrote Poème électronique for the Philips pavilion at the Brussels World Fair in 1958.

Modular synthesizers
RCA produced experimental devices to synthesize voice and music in the 1950s. The Mark II Music Synthesizer, housed at the Columbia-Princeton Electronic Music Center in New York City. Designed by Herbert Belar and Harry Olson at RCA, with contributions from Vladimir Ussachevsky and Peter Mauzey, it was installed at Columbia University in 1957. Consisting of a room-sized array of interconnected sound synthesis components, it was only capable of producing music by programming, using a paper tape sequencer punched with holes to control pitch sources and filters, similar to a mechanical player piano but capable of generating a wide variety of sounds. The vacuum tube system had to be patched to create timbres.

In the 1960s synthesizers were still usually confined to studios due to their size. They were usually modular in design, their stand-alone signal sources and processors connected with patch cords or by other means and controlled by a common controlling device. Harald Bode, Don Buchla, Hugh Le Caine, Raymond Scott and Paul Ketoff were among the first to build such instruments, in the late 1950s and early 1960s. Buchla later produced a commercial modular synthesizer, the Buchla Music Easel. Robert Moog, who had been a student of Peter Mauzey and one of the RCA Mark II engineers, created a synthesizer that could reasonably be used by musicians, designing the circuits while he was at Columbia-Princeton. The Moog synthesizer was first displayed at the Audio Engineering Society convention in 1964. It required experience to set up sounds but was smaller and more intuitive than what had come before, less like a machine and more like a musical instrument. Moog established standards for control interfacing, using a logarithmic 1-volt-per-octave for pitch control and a separate triggering signal. This standardization allowed synthesizers from different manufacturers to operate simultaneously. Pitch control was usually performed either with an organ-style keyboard or a music sequencer producing a timed series of control voltages. During the late 1960s hundreds of popular recordings used Moog synthesizers. Other early commercial synthesizer manufacturers included ARP, who also started with modular synthesizers before producing all-in-one instruments, and British firm EMS.

Integrated synthesizers
In 1970, Moog designed the Minimoog, a non-modular synthesizer with a built-in keyboard. The analogue circuits were interconnected with switches in a simplified arrangement called "normalization." Though less flexible than a modular design, normalization made the instrument more portable and easier to use. The Minimoog sold 12,000 units. Further standardized the design of subsequent synthesizers with its integrated keyboard, pitch and modulation wheels and VCO->VCF->VCA signal flow. It has become celebrated for its "fat" sound—and its tuning problems. Miniaturized solid-state components allowed synthesizers to become self-contained, portable instruments that soon appeared in live performance and quickly became widely used in popular music and electronic art music.

Polyphony
Many early analog synthesizers were monophonic, producing only one tone at a time. Popular monophonic synthesizers include the Moog Minimoog. A few, such as the Moog Sonic Six, ARP Odyssey and EML 101, could produce two different pitches at a time when two keys were pressed. Polyphony (multiple simultaneous tones, which enables chords) was only obtainable with electronic organ designs at first. Popular electronic keyboards combining organ circuits with synthesizer processing included the ARP Omni and Moog's Polymoog and Opus 3.

By 1976 affordable polyphonic synthesizers began to appear, such as the Yamaha CS-50, CS-60 and CS-80, the Sequential Circuits Prophet-5 and the Oberheim Four-Voice. These remained complex, heavy and relatively costly. The recording of settings in digital memory allowed storage and recall of sounds. The first practical polyphonic synth, and the first to use a microprocessor as a controller, was the Sequential Circuits Prophet-5 introduced in late 1977. For the first time, musicians had a practical polyphonic synthesizer that could save all knob settings in computer memory and recall them at the touch of a button. The Prophet-5's design paradigm became a new standard, slowly pushing out more complex and recondite modular designs.

Tape recording
In 1935, another significant development was made in Germany. Allgemeine Elektricitäts Gesellschaft (AEG) demonstrated the first commercially produced magnetic tape recorder, called the Magnetophon. Audio tape, which had the advantage of being fairly light as well as having good audio fidelity, ultimately replaced the bulkier wire recorders.

The term "electronic music" (which first came into use during the 1930s) came to include the tape recorder as an essential element: "electronically produced sounds recorded on tape and arranged by the composer to form a musical composition". It was also indispensable to Musique concrète.

Tape also gave rise to the first, analogue, sample-playback keyboards, the Chamberlin and its more famous successor the Mellotron, an electro-mechanical, polyphonic keyboard originally developed and built in Birmingham, England in the early 1960s.

Sound sequencer

During the 1940s–1960s, Raymond Scott, an American composer of electronic music, invented various kind of music sequencers for his electric compositions. Step sequencers played rigid patterns of notes using a grid of (usually) 16 buttons, or steps, each step being 1/16 of a measure. These patterns of notes were then chained together to form longer compositions. Software sequencers were continuously utilized since the 1950s in the context of computer music, including computer-played music (software sequencer), computer-composed music (music synthesis), and computer sound generation (sound synthesis).

Digital synthesis
The first digital synthesizers were academic experiments in sound synthesis using digital computers. FM synthesis was developed for this purpose; as a way of generating complex sounds digitally with the smallest number of computational operations per sound sample. In 1983 Yamaha introduced the first stand-alone digital synthesizer, the DX-7. It used frequency modulation synthesis (FM synthesis), first developed by John Chowning at Stanford University during the late sixties. Chowning exclusively licensed his FM synthesis patent to Yamaha in 1975. Yamaha subsequently released their first FM synthesizers, the GS-1 and GS-2, which were costly and heavy. There followed a pair of smaller, preset versions, the CE20 and CE25 Combo Ensembles, targeted primarily at the home organ market and featuring four-octave keyboards. Yamaha's third generation of digital synthesizers was a commercial success; it consisted of the DX7 and DX9 (1983). Both models were compact, reasonably priced, and dependent on custom digital integrated circuits to produce FM tonalities. The DX7 was the first mass market all-digital synthesizer. It became indispensable to many music artists of the 1980s, and demand soon exceeded supply. The DX7 sold over 200,000 units within three years.

The DX series was not easy to program but offered a detailed, percussive sound that led to the demise of the electro-mechanical Rhodes piano, which was heavier and larger than a DX synth. Following the success of FM synthesis Yamaha signed a contract with Stanford University in 1989 to develop digital waveguide synthesis, leading to the first commercial physical modeling synthesizer, Yamaha's VL-1, in 1994. The DX-7 was affordable enough for amateurs and young bands to buy, unlike the costly synthesizers of previous generations, which were mainly used by top professionals.

Sampling
The Fairlight CMI (Computer Musical Instrument), the first polyphonic digital sampler, was the harbinger of sample-based synthesizers. Designed in 1978 by Peter Vogel and Kim Ryrie and based on a dual microprocessor computer designed by Tony Furse in Sydney, Australia, the Fairlight CMI gave musicians the ability to modify volume, attack, decay, and use special effects like vibrato. Sample waveforms could be displayed on-screen and modified using a light pen. The Synclavier from New England Digital was a similar system. Jon Appleton (with Jones and Alonso) invented the Dartmouth Digital Synthesizer, later to become the New England Digital Corp's Synclavier. The Kurzweil K250, first produced in 1983, was also a successful polyphonic digital music synthesizer, noted for its ability to reproduce several instruments synchronously and having a velocity-sensitive keyboard.

Computer music
An important new development was the advent of computers for the purpose of composing music, as opposed to manipulating or creating sounds. Iannis Xenakis began what is called musique stochastique, or stochastic music, which is a method of composing that employs mathematical probability systems. Different probability algorithms were used to create a piece under a set of parameters. Xenakis used graph paper and a ruler to aid in calculating the velocity trajectories of glissando for his orchestral composition Metastasis (1953–54), but later turned to the use of computers to compose pieces like ST/4 for string quartet and ST/48 for orchestra (both 1962).

The impact of computers continued in 1956. Lejaren Hiller and Leonard Issacson composed Illiac Suite for string quartet, the first complete work of computer-assisted composition using algorithmic composition.

In 1957, Max Mathews at Bell Lab wrote MUSIC-N series, a first computer program family for generating digital audio waveforms through direct synthesis. Then Barry Vercoe wrote MUSIC 11 based on MUSIC IV-BF, a next-generation music synthesis program (later evolving into csound, which is still widely used).

In mid 80s, Miller Puckette at IRCAM developed graphic signal-processing software for 4X called Max (after Max Mathews), and later ported it to Macintosh (with Dave Zicarelli extending it for Opcode ) for real-time MIDI control, bringing algorithmic composition availability to most composers with modest computer programming background.

MIDI

In 1980, a group of musicians and music merchants met to standardize an interface by which new instruments could communicate control instructions with other instruments and the prevalent microcomputer. This standard was dubbed MIDI (Musical Instrument Digital Interface). A paper was authored by Dave Smith of Sequential Circuits and proposed to the Audio Engineering Society in 1981. Then, in August 1983, the MIDI Specification 1.0 was finalized.

The advent of MIDI technology allows a single keystroke, control wheel motion, pedal movement, or command from a microcomputer to activate every device in the studio remotely and in synchrony, with each device responding according to conditions predetermined by the composer.

MIDI instruments and software made powerful control of sophisticated instruments easily affordable by many studios and individuals. Acoustic sounds became reintegrated into studios via sampling and sampled-ROM-based instruments.

Modern electronic musical instruments
The increasing power and decreasing cost of sound-generating electronics (and especially of the personal computer), combined with the standardization of the MIDI and Open Sound Control musical performance description languages, has facilitated the separation of musical instruments into music controllers and music synthesizers.

By far the most common musical controller is the musical keyboard. Other controllers include the radiodrum, Akai's EWI and Yamaha's WX wind controllers, the guitar-like SynthAxe, the BodySynth, the Buchla Thunder, the Continuum Fingerboard, the Roland Octapad, various isomorphic keyboards including the Thummer, and Kaossilator Pro, and kits like I-CubeX.

Reactable

The Reactable is a round translucent table with a backlit interactive display. By placing and manipulating blocks called tangibles on the table surface, while interacting with the visual display via finger gestures, a virtual modular synthesizer is operated, creating music or sound effects.

Percussa AudioCubes

AudioCubes are autonomous wireless cubes powered by an internal computer system and rechargeable battery. They have internal RGB lighting, and are capable of detecting each other's location, orientation and distance. The cubes can also detect distances to the user's hands and fingers. Through interaction with the cubes, a variety of music and sound software can be operated. AudioCubes have applications in sound design, music production, DJing and live performance.

Kaossilator

The Kaossilator and Kaossilator Pro are compact instruments where the position of a finger on the touch pad controls two note-characteristics; usually the pitch is changed with a left-right motion and the tonal property, filter or other parameter changes with an up-down motion. The touch pad can be set to different musical scales and keys. The instrument can record a repeating loop of adjustable length, set to any tempo, and new loops of sound can be layered on top of existing ones. This lends itself to electronic dance-music but is more limited for controlled sequences of notes, as the pad on a regular Kaossilator is featureless.

Eigenharp
The Eigenharp is a large instrument resembling a bassoon, which can be interacted with through big buttons, a drum sequencer and a mouthpiece. The sound processing is done on a separate computer.

AlphaSphere
The AlphaSphere is a spherical instrument that consists of 48 tactile pads that respond to pressure as well as touch. Custom software allows the pads to be indefinitely programmed individually or by groups in terms of function, note, and pressure parameter among many other settings. The primary concept of the AlphaSphere is to increase the level of expression available to electronic musicians, by allowing for the playing style of a musical instrument.

Chip music
Chiptune, chipmusic, or chip music is music written in sound formats where many of the sound textures are synthesized or sequenced in real time by a computer or video game console sound chip, sometimes including sample-based synthesis and low bit sample playback. Many chip music devices featured synthesizers in tandem with low rate sample playback.

DIY culture
During the late 1970s and early 1980s, do-it-yourself designs were published in hobby electronics magazines (such the Formant modular synth, a DIY clone of the Moog system, published by Elektor) and kits were supplied by companies such as Paia in the US, and Maplin Electronics in the UK.

Circuit bending

In 1966, Reed Ghazala discovered and began to teach math "circuit bending"—the application of the creative short circuit, a process of chance short-circuiting, creating experimental electronic instruments, exploring sonic elements mainly of timbre and with less regard to pitch or rhythm, and influenced by John Cage’s aleatoric music concept.

Much of this manipulation of circuits directly, especially to the point of destruction, was pioneered by Louis and Bebe Barron in the early 1950s, such as their work with John Cage on the Williams Mix and especially in the soundtrack to Forbidden Planet.

Modern circuit bending is the creative customization of the circuits within electronic devices such as low voltage, battery-powered guitar effects, children's toys and small digital synthesizers to create new musical or visual instruments and sound generators. Emphasizing spontaneity and randomness, the techniques of circuit bending have been commonly associated with noise music, though many more conventional contemporary musicians and musical groups have been known to experiment with "bent" instruments. Circuit bending usually involves dismantling the machine and adding components such as switches and potentiometers that alter the circuit. With the revived interest for analogue synthesizer circuit bending became a cheap solution for many experimental musicians to create their own individual analogue sound generators. Nowadays many schematics can be found to build noise generators such as the Atari Punk Console or the Dub Siren as well as simple modifications for children toys such as the Speak & Spell that are often modified by circuit benders.

Modular synthesizers
The modular synthesizer is a type of synthesizer consisting of separate interchangeable modules. These are also available as kits for hobbyist DIY constructors. Many hobbyist designers also make available bare PCB boards and front panels for sale to other hobbyists.

DIY

 * DIY Hardware and Software Discussion forum at Electro-music.com
 * The Synth-DIY email list
 * Music From Outer Space Information and parts to self-build a synthesizer.
 * Synthesizer do it yourself a wiki about DIY electronic musical instruments

Museums and collections

 * Horniman Museum's music gallery, London, UK. Has one or two synths behind glass.
 * Moogseum, Asheville, North Carolina, US
 * Musical Museum, Brentford, London, UK. Mostly electro-mechanical instruments.
 * Musical Instrument Museum, Phoenix, Arizona, US
 * Staatliches Institut für Musikforschung, Berlin, Germany
 * Swiss Museum & Center for Electronic Music Instruments
 * The National Music Centre Collection, Canada
 * Vintage Synthesizer Museum, California, US
 * Washington And Lee University Synthesizer Museum, Washington, US

title: Electronic musical instrument


text:
Electrode

An electrode is an electrical conductor used to make contact with a nonmetallic part of a circuit (e.g. a semiconductor, an electrolyte, a vacuum or air). Electrodes are essential parts of batteries that can consist of a variety of materials depending on the type of battery.

The electrophore, invented by Johan Wilcke, was an early version of an electrode used to study static electricity.

Anode and cathode in electrochemical cells

Electrodes are an essential part of any battery. The first electrochemical battery was devised by Alessandro Volta and was aptly named the Voltaic cell. This battery consisted of a stack of copper and zinc electrodes separated by brine-soaked paper disks. Due to fluctuation in the voltage provided by the voltaic cell, it was not very practical. The first practical battery was invented in 1839 and named the Daniell cell after John Frederic Daniell. It still made use of the zinc–copper electrode combination. Since then, many more batteries have been developed using various materials. The basis of all these is still using two electrodes, anodes and cathodes.

Anode
'Anode' was coined by William Whewell at Michael Faraday's request, derived from the Greek words ἄνο (ano), 'upwards' and ὁδός (hodós), 'a way'. The anode is the electrode through which the conventional current enters from the electrical circuit of an electrochemical cell (battery) into the non-metallic cell. The electrons then flow to the other side of the battery. Benjamin Franklin surmised that the electrical flow moved from positive to negative. The electrons flow away from the anode and the conventional current towards it. From both can be concluded that the charge of the anode is negative. The electron entering the anode comes from the oxidation reaction that takes place next to it.

Cathode
The cathode is in many ways the opposite of the anode. The name (also coined by Whewell) comes from the Greek words κάτω (kato), 'downwards' and ὁδός (hodós), 'a way'. It is the positive electrode, meaning the electrons flow from the electrical circuit through the cathode into the non-metallic part of the electrochemical cell. At the cathode, the reduction reaction takes place with the electrons arriving from the wire connected to the cathode and are absorbed by the oxidizing agent.

Primary cell

A primary cell is a battery designed to be used once and then discarded. This is due to the electrochemical reactions taking place at the electrodes in the cell not being reversible. An example of a primary cell is the discardable alkaline battery commonly used in flashlights. Consisting of a zinc anode and a manganese oxide cathode in which ZnO is formed. The half-reactions are:
 * Zn(s) + 2OH−(aq) → ZnO(s) + H2O(l) + 2e− $$\qquad \qquad$$ [E0oxidation = -1.28 V]
 * 2MnO2(s) + H2O(l) + 2e− → Mn2O3(s) + 2OH−(aq)$$\qquad$$ [E0reduction = +0.15 V]

Overall reaction:
 * Zn(s) + 2MnO2(s) ZnO(s) + Mn2O3(s)$$\qquad \qquad$$ [E0total = +1.43 V]

The ZnO is prone to clumping and will give less efficient discharge if recharged again. It is possible to recharge these batteries but is due to safety concerns advised against by the manufacturer. Other primary cells include zinc–carbon, zinc–chloride, and lithium iron disulfide.

Secondary cell

Contrary to the primary cell a secondary cell can be recharged. The first was the lead–acid battery, invented in 1859 by French physicist Gaston Planté. This type of battery is still the most widely used in among others automobiles. The cathode consists of lead dioxide (PbO2) and the anode of solid lead. Other commonly used rechargeable batteries are nickel–cadmium, nickel–metal hydride, and Lithium-ion. The last of which will be explained more thoroughly in this article due to its importance.

Marcus' theory of electron transfer
Marcus theory is a theory originally developed by Nobel laureate Rudolph A. Marcus and explains the rate at which an electron can move from one chemical species to another, for this article this can be seen as 'jumping' from the electrode to a species in the solvent or vice versa. We can represent the problem as calculating the transfer rate for the transfer of an electron from donor to an acceptor
 * D + A → D+ + A−

The potential energy of the system is a function of the translational, rotational, and vibrational coordinates of the reacting species and the molecules of the surrounding medium, collectively called the reaction coordinates. The abscissa the figure to the right represents these. From the classical electron transfer theory, the expression of the reaction rate constant (probability of reaction) can be calculated, if a non-adiabatic process and parabolic potential energy are assumed, by finding the point of intersection (Qx). One important thing to note, and was noted by Marcus when he came up with the theory, the electron transfer must abide by the law of conservation of energy and the Frank-Condon principle. Doing this and then rearranging this leads to the expression of the free energy activation ($$\Delta G^{\dagger}$$) in terms of the overall free energy of the reaction ($$\Delta G^{0}$$). $$\Delta G^{\dagger} = \frac{1}{4 \lambda} (\Delta G^{0} + \lambda)^{2} $$

In which the $$ \lambda $$ is the reorganisation energy. Filling this result in the classically derived Arrhenius equation

$$k = A\, \exp\left(\frac{- \Delta G^{\dagger}}{kT}\right),$$

leads to

$$k = A\, \exp\left[{\frac {-(\Delta G^{0} + \lambda)^{2}}{4 \lambda k T}}\right]$$

With A being the pre-exponential factor which is usually experimentally determined, although a semi classical derivation provides more information as will be explained below.

This classically derived result qualitatively reproduced observations of a maximum electron transfer rate under the conditions $$\Delta G^{\dagger} = \lambda$$. For a more extensive mathematical treatment one could read the paper by Newton. An interpretation of this result and what a closer look at the physical meaning of the $$\lambda$$ one can read the paper by Marcus.

the situation at hand can be more accurately described by using the displaced harmonic oscillator model, in this model quantum tunneling is allowed. This is needed in order to explain why even at near-zero Kelvin there still are electron transfers, in contradiction to the classical theory.

Without going into too much detail on how the derivation is done, it rests on using Fermi's golden rule from time-dependent perturbation theory with the full Hamiltonian of the system. It is possible to look at the overlap in the wavefunctions of both the reactants and the products (the right and the left side of the chemical reaction) and therefore when their energies are the same and allow for electron transfer. As touched on before this must happen because only then conservation of energy is abided by. Skipping over a few mathematical steps the probability of electron transfer can be calculated (albeit quite difficult) using the following formula

$$w_{ET}= \frac{|J|^{2}}{\hbar^{2}}\int_{-\infty}^{+\infty}dt\, e^{-i \Delta Et / \hbar - g (t)}$$

With $$ J $$ being the electronic coupling constant describing the interaction between the two states (reactants and products) and $$ g(t) $$ being the line shape function. Taking the classical limit of this expression, meaning $$ \hbar \omega \ll k T $$, and making some substitution an expression is obtained very similar to the classically derived formula, as expected. $$w_{ET} = \frac{|J|^{2}}{\hbar} \sqrt{\frac{\pi}{\lambda k T}}\exp\left[\frac {- ( \Delta E + \lambda )^{2}} {4 \lambda k T}\right]$$

The main difference is now the pre-exponential factor has now been described by more physical parameters instead of the experimental factor $$ A $$. One is once again revered to the sources as listed below for a more in-depth and rigorous mathematical derivation and interpretation.

Efficiency
The physical properties of electrodes are mainly determined by the material of the electrode and the topology of the electrode. The properties required depend on the application and therefore there are many kinds of electrodes in circulation. The defining property for a material to be used as an electrode is that it be conductive. Any conducting material such as metals, semiconductors, graphite or conductive polymers can therefore be used as an electrode. Often electrodes consist of a combination of materials, each with a specific task. Typical constituents are the active materials which serve as the particles which oxidate or reduct, conductive agents which improve the conductivity of the electrode and binders which are used to contain the active particles within the electrode. The efficiency of electrochemical cells is judged by a number of properties, important quantities are the self-discharge time, the discharge voltage and the cycle performance. The physical properties of the electrodes play an important role in determining these quantities. Important properties of the electrodes are: the electrical resistivity, the specific heat capacity (c_p), the electrode potential and the hardness. Of course, for technological applications, the cost of the material is also an important factor. The values of these properties at room temperature (T = 293 K) for some commonly used materials are listed in the table below.

Surface effects
The surface topology of the electrode plays an important role in determining the efficiency of an electrode. The efficiency of the electrode can be reduced due to contact resistance. To create an efficient electrode it is therefore important to design it such that it minimizes the contact resistance.

Manufacturing
The production of electrodes for Li-ion batteries is done in various steps as follows:
 * 1) The various constituents of the electrode are mixed into a solvent. This mixture is designed such that it improves the performance of the electrodes. Common components of this mixture are:
 * 2) * The active electrode particles.
 * 3) * A binder used to contain the active electrode particles.
 * 4) * A conductive agent used to improve the conductivity of the electrode.
 * The mixture created is known as an ‘electrode slurry’.
 * 1) The electrode slurry above is coated onto a conductor which acts as the current collector in the electrochemical cell. Typical current collectors are copper for the cathode and aluminum for the anode.
 * 2) After the slurry has been applied to the conductor it is dried and then pressed to the required thickness.

Structure of the electrode
For a given selection of constituents of the electrode, the final efficiency is determined by the internal structure of the electrode. The important factors in the internal structure in determining the performance of the electrode are:
 * Clustering of the active material and the conductive agent. In order for all the components of the slurry to perform their task, they should all be spread out evenly within the electrode.
 * An even distribution of the conductive agent over the active material. This makes sure that the conductivity of the electrode is optimal.
 * The adherence of the electrode to the current collectors. The adherence makes sure that the electrode does not dissolve into the electrolyte.
 * The density of the active material. A balance should be found between the amount of active material, the conductive agent and the binder. Since the active material is the important factor in the electrode, the slurry should be designed such that the density of the active material is as high as possible, without the conductive agent and the binder not functioning properly.

These properties can be influenced in the production of the electrodes in a number of manners. The most important step in the manufacturing of the electrodes is creating the electrode slurry. As can be seen above, the important properties of the electrode all have to do with the even distribution of the components of the electrode. Therefore, it is very important that the electrode slurry be as homogeneous as possible. Multiple procedures have been developed to improve this mixing stage and current research is still being done.

Electrodes in lithium ion batteries
A modern application of electrodes is in lithium-ion batteries (Li-ion batteries). A Li-ion battery is a kind of flow battery which can be seen in the image on the right.

Furthermore, a Li-ion battery is an example of a secondary cell since it is rechargeable. It can both act as a galvanic or electrolytic cell. Li-ion batteries use lithium ions as the solute in the electrolyte which are dissolved in an organic solvent. Lithium electrodes were first studied by Gilbert N. Lewis and Frederick G. Keyes in 1913. In the following century these electrodes were used to create and study the first Li-ion batteries. Li-ion batteries are very popular due to their great performance. Applications include mobile phones and electric cars. Due to their popularity, much research is being done to reduce the cost and increase the safety of Li-ion batteries. An integral part of the Li-ion batteries are their anodes and cathodes, therefore much research is being done into increasing the efficiency, safety and reducing the costs of these electrodes specifically.

Cathodes
In Li-ion batteries, the cathode consists of a intercalated lithium compound (a layered material consisting of layers of molecules composed of lithium and other elements). A common element which makes up part of the molecules in the compound is cobalt. Another frequently used element is manganese. The best choice of compound usually depends on the application of the battery. Advantages for cobalt-based compounds over manganese-based compounds are their high specific heat capacity, high volumetric heat capacity, low self-discharge rate, high discharge voltage and high cycle durability. There are however also drawbacks in using cobalt-based compounds such as their high cost and their low thermostability. Manganese has similar advantages and a lower cost, however there are some problems associated with using manganese. The main problem is that manganese tends to dissolve into the electrolyte over time. For this reason, cobalt is still the most common element which is used in the lithium compounds. There is much research being done into finding new materials which can be used to create cheaper and longer lasting Li-ion batteries

Anodes
The anodes used in mass-produced Li-ion batteries are either carbon based (usually graphite) or made out of spinel lithium titanate (Li4Ti5O12). Graphite anodes have been successfully implemented in many modern commercially available batteries due to its cheap price, longevity and high energy density. However, it presents issues of dendrite growth, with risks of shorting the battery and posing a safety issue. Li4Ti5O12 has the second largest market share of anodes, due to its stability and good rate capability, but with challenges such as low capacity. During the early 2000s, silicon anode research began picking up pace, becoming one of the decade's most promising candidates for future lithium-ion battery anodes. Silicon has one of the highest gravimetric capacities when compared to graphite and Li4Ti5O12 as well as a high volumetric one. Furthermore, Silicon has the advantage of operating under a reasonable open circuit voltage without parasitic lithium reactions. However, silicon anodes have a major issue of volumetric expansion during lithiation of around 360%. This expansion may pulverize the anode, resulting in poor performance. To fix this problem, scientists looked into varying the dimensionality of the Si. Many studies have been developed in Si nanowires, Si tubes as well as Si sheets. As a result, composite hierarchical Si anodes have become the major technology for future applications in lithium-ion batteries. In the early 2020s, technology is reaching commercial levels with factories being built for mass production of anodes in the United States. Furthermore, metallic lithium is another possible candidate for the anode. It boasts a higher specific capacity than silicon, however, does come with the drawback of working with the highly unstable metallic lithium. Similarly to graphite anodes, dendrite formation is another major limitation of metallic lithium, with the solid electrolyte interphase being a major design challenge. In the end, if stabilized, metallic lithium would be able to produce batteries that hold the most charge, while being the lightest.

Mechanical properties
A common failure mechanism of batteries is mechanical shock, which breaks either the electrode or the system's container, leading to poor conductivity and electrolyte leakage. However, the relevance of mechanical properties of electrodes goes beyond the resistance to collisions due to its environment. During standard operation, the incorporation of ions into electrodes leads to a change in volume. This is well exemplified by Si electrodes in lithium-ion batteries expanding around 300% during lithiation. Such change may lead to the deformations in the lattice and, therefore stresses in the material. The origin of stresses may be due to geometric constraints in the electrode or inhomogeneous plating of the ion. This phenomenon is very concerning as it may lead to electrode fracture and performance loss. Thus, mechanical properties are crucial to enable the development of new electrodes for long lasting batteries. A possible strategy for measuring the mechanical behavior of electrodes during operation is by using nanoindentation. The method is able to analyze how the stresses evolve during the electrochemical reactions, being a valuable tool in evaluating possible pathways for coupling mechanical behavior and electrochemistry.

More than just affecting the electrode's morphology, stresses are also able to impact electrochemical reactions. While the chemical driving forces are usually higher in magnitude than the mechanical energies, this is not true for Li-ion batteries. A study by Dr. Larché established a direct relation between the applied stress and the chemical potential of the electrode. Though it neglects multiple variables such as the variation of elastic constraints, it subtracts from the total chemical potential the elastic energy induced by the stress.

$$\mu = \mu^o + k\cdot T\cdot\log (\gamma\cdot x) + \Omega \cdot \sigma$$

In this equation, μ represents the chemical potential, with μ° being its reference value. T stands for the temperature and k the Boltzmann constant. The term γ inside the logarithm is the activity and x is the ratio of the ion to the total composition of the electrode. The novel term Ω is the partial molar volume of the ion in the host and σ corresponds to the mean stress felt by the system. The result of this equation is that diffusion, which is dependent on chemical potential, gets impacted by the added stress and, therefore changes the battery's performance. Furthermore, mechanical stresses may also impact the electrode's solid-electrolyte-interphase layer. The interface which regulates the ion and charge transfer and can be degraded by stress. Thus, more ions in the solution will be consumed to reform it, diminishing the overall efficiency of the system.

Other anodes and cathodes
In a vacuum tube or a semiconductor having polarity (diodes, electrolytic capacitors) the anode is the positive (+) electrode and the cathode the negative (−). The electrons enter the device through the cathode and exit the device through the anode. Many devices have other electrodes to control operation, e.g., base, gate, control grid.

In a three-electrode cell, a counter electrode, also called an auxiliary electrode, is used only to make a connection to the electrolyte so that a current can be applied to the working electrode. The counter electrode is usually made of an inert material, such as a noble metal or graphite, to keep it from dissolving.

Welding electrodes
In arc welding, an electrode is used to conduct current through a workpiece to fuse two pieces together. Depending upon the process, the electrode is either consumable, in the case of gas metal arc welding or shielded metal arc welding, or non-consumable, such as in gas tungsten arc welding. For a direct current system, the weld rod or stick may be a cathode for a filling type weld or an anode for other welding processes. For an alternating current arc welder, the welding electrode would not be considered an anode or cathode.

Alternating current electrodes
For electrical systems which use alternating current, the electrodes are the connections from the circuitry to the object to be acted upon by the electric current but are not designated anode or cathode because the direction of flow of the electrons changes periodically, usually many times per second.

Chemically modified electrodes
Chemically modified electrodes are electrodes that have their surfaces chemically modified to change the electrode's physical, chemical, electrochemical, optical, electrical, and transportive properties. These electrodes are used for advanced purposes in research and investigation.

Uses
Electrodes are used to provide current through nonmetal objects to alter them in numerous ways and to measure conductivity for numerous purposes. Examples include:
 * Electrodes for fuel cells
 * Electrodes for medical purposes, such as EEG (for recording brain activity), ECG (recording heart beats), ECT (electrical brain stimulation), defibrillator (recording and delivering cardiac stimulation)
 * Electrodes for electrophysiology techniques in biomedical research
 * Electrodes for execution by the electric chair
 * Electrodes for electroplating
 * Electrodes for arc welding
 * Electrodes for cathodic protection
 * Electrodes for grounding
 * Electrodes for chemical analysis using electrochemical methods
 * Nanoelectrodes for high-precision measurements in nanoelectrochemistry
 * Inert electrodes for electrolysis (made of platinum)
 * Membrane electrode assembly
 * Electrodes for Taser electroshock weapon

title: Electrode