Yishay Mor

Celia Hoyles

Ken Kahn

Richard Noss

Gordon Simpson

This article tells the story of 11-14 year-o l d students using a rather new and re l a t i v e l y untested programming system to represent and discuss some deep mathematical ideas. There is one caveat: we have chosen the episodes to indicate the possibilities that can emerge when children are given new ways to talk and think about mathematics. We cannot lay claim to any generality: we would invite the reader to look where we are pointing, not at our fingers! We are programming with ToonTalk, a language we have used in the past with younger children to c o n s t ruct video games, and which we have written about previously in Micromath. ToonTalk is a computer game, programming environment and programming language in one. In most languages, p rogramming means writing text (code) in a highly stru c t u red syntax. Some enviro n m e n t s allow the user to replace pieces of this text with iconic representations. But ToonTalk takes this one stage further, in that programs take the form of animated cartoon robots (ToonTalk is so named because one is "talking" in (car)toons). Programming is done by training these robots, leading them through the task they are meant to perform. After training, programs are generalised by "erasing" superfluous detail from ro b o t s ' "minds" (to train a robot, you just go in and program an example in its thought bubble!).

So the process of what it means to program is very

Train the robot to take a number 1 from the toolbox and drop it on the input, to increment it. Generalise the program by erasing the value of the input from the robots memory.

Give the robot its input box. The robot will continuously repeat the actions it has been taught. From these, we were able to identify five basic contexts for the use of IWB.

q Teacher as demonstrator q Teacher as modeller q Teacher in control -inviting the pupils (shared) q Pupils in control with the "teacher" advising (guided) q Pupils working independently Demonstration was used to describe teacher input that simply demonstrated the mathematical process e.g. how to add two 3 digit numbers, or s o f t w a re features. Modelling suggests the modelling of mathematical thinking with the aid of the IWB software (metacognitive modelling). Sharing occurs when the teacher has control of the IWB but invites pupils to participate in a task. Guided use refers to pupils leading with guidance from the teacher concerning content, direction or technical issues. Pupils can work independently, either in small groups or alone on IWB. The size of the image and the interactivity means small groups can share ideas with greater ease than if they were sitting around a single computer screen.

Implications for the teachers involved in the project

The teachers adopted models for the use of the t e c h n o l o g y, at least initially, in a way in which they felt most comfortable. Although the IWB was felt to change the flow, content and pace of the lessons, to begin to use it, teachers did not feel that they had to make large shifts in their classroom practice.

Whilst the teachers recognised the first two teaching contexts, demonstrating and modelling, as part of their general classroom practice they could offer little anecdotal evidence of pupils participating in any form beyond the "come up and show us" model in the whole class activities at the start and end of the numeracy lesson. The identification of the lack of pupil involvement led to discussion about teachers' everyday IWB practice. As a consequence, teachers considered the need to expand the sphere of influence of the IWB into parts of the lesson where they were not taking the lead.

C e rtain software encouraged the adoption of p a rticular approaches to the use of the IWB by the teachers. The majority of the software being used was for whole class-teacher centred work. Where the software had the potential for pupils working i n d e p e n d e n t l y, it re q u i red additional impetus for change. Even when the software had the potential to support pupils working independently this facility was not utilised. The following examples in F i g u re 1 are those that the teachers came up with in the session. They are not necessarily pre s e n t e d as the best practice in these areas.

Although the purpose of this article has not been to discuss the role of alternative means of achieving similar practices with other technologies -it does appear to be the case that the "interactiveness" of the IWB comes more into its own as you move "down" the contexts that appear in Figure 1. That is, models of teaching and learning that are more open and social are more likely to result in the IWB offering a unique feature to the classroom. By identifying a framework for "the use of the interactive whiteboard" the teachers were alerted to a wider variety of teaching and learn i n g contexts and possibilities. This has begun to influence their practice and enabled them to engage their established understanding of the flow of pupil/teacher activity in a lesson with their developing use of the IWB. The IWB thus becomes an instrument of change as it becomes more fully adopted and teachers adopt new models of c l a s s room practice that more fully utilise the potential of the whiteboard.

The mapping of a possible framework for the use of the interactive whiteboard meant that teachers now had a way to refine their re s e a rch questions so that the reader and writer could have a greater chance of having the same understanding as to how the IWB was being used, rather than relying on assumptions as discussed in our introduction. The need for such a framework is clearly evident, the one presented here is intended to stimulate debate as to the precise nature of such a framework. d i ff e rent from any existing pro g r a m m i n g language, and because programming objects are animated, it is very difficult to conjure up the feel of the process without trying it. Fortunately, this is straightforward. The important point is that the process is made concrete in a robot, which can be pointed at, named, picked up, and moved about.

Figure 1 shows three snapshots of what it means to write a program (train a robot) to count through the natural numbers. In fact, we only have to train the robot to "add 1" to a number and then generalise it to any number. The robot iterates the actions it was trained to do, for as long as the conditions it expects hold. Alongside the programming system, and a set of appropriate tools developed within it, we have c o n s t ructed a web-based system we call WebReports, designed to allow students to share and discuss the models of mathematical objects and processes they have built in ToonTalk. The students use a visual on-line editor to compose reports detailing their work, can comment on and annotate each others' re p o rts, and -most importantly -can publish working ToonTalk models of their ideas as they develop. This is a simple process: students can grab any object in their ToonTalk environment, and include it in their online report. The object is shown as an image, but it is also a hyperlink, which, when clicked, causes the object to open in the ToonTalk environmentwhich could be in another classroom or another country. This last point is crucial: rather than simply discussing what each other thinks, students can share what they have built, and rebuild each others' attempts to model any given task or object. F i g u re 2 shows the welcome page of a "WebReport", seen after logging into the system. It includes a personal navigation sidebar, tabs to access general areas (such as topics and groups), and a quick view of the most recent updates.

After about a year of work, we are beginning to notice how students are starting to use their p rogrammed models as elements of their discourse. By expressing themselves through their models, they are beginning to find ways to talk Guess My Robot: Rita's challenge and Nasko's response

We now turn to the story. First, we should introduce the setting. We focus on the interactions between two groups of students, one in Sofia and the other near Lisbon. The Sofia group consists of 6 boys and girls, aged 11-12, working with WebLabs researchers. They have been working with ToonTalk for several months, approximately once a week for a couple of hours. The second group is from a village south of Lisbon. Paula, a teacher and re s e a rcher in the We b L a b s t e a m , worked there with a school group (aged 12-13) during the first project year. Researchers in both g roups act as teachers, guiding the students through the mathematical ideas as well as through the programming skills. At the same time, the re s e a rchers facilitate interactions, by pointing children to interesting peer reports and helping them to add a few words in English to their own reports.

The activity we designed was based on the wellknown "Guess my rule" game, employed by us in the context of Logo and spreadsheets, and by many teachers and researchers as a well-known activity. It has also been used in many classrooms in the UK over many years to provoke children to discuss and compare the formulation of rules, and in particular the equivalence (or not) of their algebraic symbolism. In its classical form, it has been used as an introduction to functions and to formal algebraic notation. As [START_REF] Carraher | Guess My Rule Revisited[END_REF] have recently reported, even children in younger grades enjoy participating in this game, and can be drawn into a discussion of algebraic nature through using it. It is an excellent context for students to come to understand that different articulations of their constructions can indeed yield the same results and it does this as children feel some ownership of their construction and are willing therefore to engage with others to compare and contrast solutions.

The aims of "Guess my robot" are to encourage students: to build sequences with robots and to challenge others to program the robot that made the sequence; to compare the robots used and to discuss the different methods; and to take a robot

The "Guess my Robot" game presented in a WebReport that explains the game rules. Each student creates her own game page, and the pages are listed at the bottom of the main game page.

that "encapsulates the process" and use it to generate new sequences by using new inputs.

So, in our game, proposers (students) invent a rule and program it so that it generates a numerical sequence, and publish the first few terms it generates in a WebReport. Responders then have to build a robot that will produce this sequence, and thus work out the underlying rule. The new element in our variant of the game is that "rules" have to be encoded as robots: one responds to a challenge sequence by posting a robot that produces "the same" sequence. So the encoding of the rule takes the form of a process-description in the form of a 'program'. Managing to reproduce someone else's sequence by training a robot, is a way to show that you have grasped how the sequence may have been originally generated. As one girl said:

"So, like, the robot is my proof that I got it?"

Let's go back to our story. Figure 3 shows the main "guess my robot" game page. Students enter the game via this page, where they are challenged to generate a "smart sequence" and post it on the web.

Rita is a 14 year old girl from Lisbon, who has been participating in WebLabs since February 2003. She likes maths, but has not yet learnt much about sequences in school: this topic is not highly developed in the Portuguese curriculum. In fact, most of her experience in this topic comes from her involvement with WebLabs.

Rita found the 'guess my robot' activity, and decided to pose her own challenge. The sequence she posted (see Figure 4) was:

2, 16, 72, 296, 1192 …

A few days after she posted it, the Sofia WebLabs group held a session, and some of the students tried solving Rita's challenge. Nasko, a 12 year-old boy, posted his response. He had built a robot that produced Rita's five terms, but also realised that the same robot could be used to generate other sequences by changing its initial inputs. So, he posed a two-part challenge for Rita:

q Could she use his robot to generate a new sequence of five terms? q Could she use her robot to generate the same sequence?

Nasko's response and challenge are shown in Figure 5.

Ivan, who is also a member of the Sofia group, could not participate in that particular WebLabs session. Still, that did not stop him from trying his hand at Rita's challenge, and posting his own response (Figure 6). Ivan succeeded in building a robot, but was especially proud of what he thought was a clever solution as it was 'simpler':

("I only use two holes in the box"). He adds: "I'm curious to see other solutions".

A few days later Rita came to her next session. She was very excited to find comments on her pageand from children on the other side of Europe! She immediately clicked on the ToonTalk robots in the responses, and watched them step through the p rocess of rule-generation. She was totally surprised: Nasko and Ivan had solved her challenge, but their robots seemed completely different from hers (and one from the other)! When this cycle completes, the number in the leftmost box is then passed to the "bird", as a second element of the sequence, starting the second cycle.

A "bird" is the way that To o n Ta l k uses to communicate between objects. In this case, it takes the number of the sequence in turn, and collects them (on its nest!).

Rita's robot therefore computes:

An+1 = (An +2) *4 A1 = 2
Nasko's robot (Figure 8) differs from Rita's in two respects. Firstly, its programming style is different; while Rita uses a bird to carry the sequence elements out, Nasko displays them in the robot's box. The second disparity is more interesting -the robot appears at first sight to be computing a completely different sequence! Nasko's robot computes:

An= An -1 +14) *4 n -2 A1 = 2
Are these two robots equivalent? And what, in any case, does "equivalent" mean (this in itself is an interesting talking point for the two children concerned). This may be an interesting exercise in algebra for the reader.

Copy the value of An to the bird, to send it out, so the first term is the number in the left-most box.

Copy the value of i (14) over the current sequence term (2), adding them up.

Copy the value of j (*4) over i, multiplying it by 4.

Copy i (2) and place on top of An, which adds 2 to it.

Copy k (*4) on to An, multiplying it by 4. The next step

Now that something unexpected has happened, the next step is to challenge the students to explain it. Both groups are scheduled to discuss the different solutions, compare them and explain how they appear to generate the same sequence. The questions they will discuss include:

q Explain how you worked out what the sequence was, and how you ended up with the robot you built.

q We think your robots will generate the same sequence forever, but how can we be sure?

q Discuss the different robots, and explain why they seem to generate the same sequence.

q Describe what the robots are doing on the whiteboard or on paper, in a way that will make it easier to compare them.

As at the previous stage, we are planning for surprises. We designed the original challenge in the belief that responders would solve the same task differently from proposers, and that both sides would find this interesting enough to have a mathematical discussion. This time, we're prepared to be as surprised as the students. Will they base their explanations on the ToonTalk representation, or will they ask for alternative notations? In either case they will be exploring new mathematical terrain. The objects of discussion have emerged from their own activities. This sense of ownership allows, we believe, children to access structures and ideas which may normally be considered too advanced for them. If this is the case, although the ToonTalk representation cannot help furnish the proof, it may be a useful tool in motivating an interesting and non-trivial piece of mathematical p roblem-posing (the situation is somewhat analogous to that of Dynamic Geometry in this respect).

We do not mean to restrict the role of programming to a matter of motivation. We wrote "the robot computes the sequence…". In fact, we should have written "The robot IS the sequence…" in the same way as we talk of "the sequence An= a + b * n ". The same sequence can be represented as "An= An-1+b; A1= a" or by the robot with a 3-hole box. All three notations are valid, precise and well-defined. Just as a formal equation defines a unique sequence, or class of sequences, so does a ToonTalk robot.

As mathematically-educated people, we may take for granted the meaning of a statement like An= a+ b*n. In much the same way, participants in To illustrate this point, we focus on Rita's response to Nasko's challenge. Nasko had challenged Rita to the use the robot he had constructed for her sequence 2, 16, 72, 296, 1192,... to generate another sequence: 9.5, 14, 16.25, 17.375, 17.9375 Rita responds to Nasko by comparing each step of the process that the robot acted out, and imagining what numbers the robot must have worked on, in order to obtain the required number:

"In Nasko's box for my sequence he used 2 in the first hole, and added 14 from the second hole to get the second term ( 16), and multiplies that by 4. Then I think to get the first term of Nasko's sequence I need 9.5 in the first hole. The number in the second hole has to be a number that you add to 9.5 to get 14 (the second term), this number is 4.5. In my sequence he uses x4 to get the third term (16 + 14 x 4). Then for his sequence I think like this: 14 + 4.5 "something" should give me 16.25, or 4.5 "something" should give me 2.25. But 2.25 is half of 4.5, then in third hole of the box I need to put /2".

Does this count as a mathematical solution? We leave it to the reader to decide.

Figure 1 :

 1 Figure 1: Training a robot to count

  ReferenceBECTA,2004,Getting the most from your interactive whiteboard;a guide for Primary schools. Note:Easiteach Maths is an RM product used in many Primary Schools.The latest version is now part of the Easiteach Studio package. More information can be found on the RM website http://www.rm.com/rmcomhome.asp Penny Knight and Jennie Pennant work with the Bracknell Forest LEA and Jennifer Piggott works at the Faculty of Education,University of Cambridge.

Figure 2 :

 2 Figure 2: WebReports welcome page Figure 3: "Guess My Robot" WebReport pages

Figure 4 :

 4 Figure 4: Rita's "Guess My Robot" challenge

Figure 6 :

 6 Figure 6: Ivan's response to Rita

Figure 7 :

 7 Figure 7: Rita's robot in action

the

  WebLabs community are coming to share the meaning of ToonTalk robots as representations of mathematical entities. Each representation has its s t rengths. While the algebraic form is more conducive to formal manipulations and proof, the To o n Ta l k re p resentation is situated within a familiar activity, and is easier to tweak in an exploratory manner. Most important, what you "write" (i.e. do on the screen) has a real effect in terms of what the program produces (how do you know when you've got an algebraic calculation wrong?).


Laura Naismith
email: l.naismith@bham.ac.uk

Mike Sharples
email: m.sharples@bham.ac.uk

Jeffrey Ting

Evaluation of CAERUS: a Context Aware Mobile Guide

Keywords: tourism, informal learning, context aware, museum 1

This paper reports on the results of a user evaluation of CAERUS, which is a complete context aware educational resource system for outdoor tourist sites and educational centres. CAERUS consists of a handheld delivery application and a desktop administration application and provides a visual interface to add new maps, define regions of interest, add theme-based multimedia tours, and deliver this information to visitors through Pocket PC devices with GPS capability. Fourteen participants used CAERUS in the University of Birmingham's Botanic Garden at Winterbourne in May 2005. Participants reported high satisfaction with the location-based content provided, particularly the audio commentary. Significant problems with positioning and navigation were experienced, especially amongst the participants using the system in 'guided tour' mode. Younger and older visitors differed in opinion as to how easy CAERUS was to learn and the clarity of the user interface. The main effect of CAERUS with respect to learning was to increase the participants' engagement with their physical surroundings.

Introduction

The main aim of outdoor museums and field centres is to encourage learning within an authentic context (University of Birmingham 2001;Birmingham City Council 2004). Visitors are encouraged to explore and discover in order to learn the processes of inquiry and even of learning itself [START_REF] Hawkey | Learning with Digital Technologies in Museums, Science Centres and Galleries[END_REF]). Due to a lack of preparation and follow-up [START_REF] Oppermann | A Nomadic Information System for Adaptive Exhibition Guidance[END_REF] and supporting materials that cannot easily adapt to the range of visitor interests and needs [START_REF] Not | Content Adaptation for Audio-based Hypertexts in Physical Environments[END_REF], visitors often do not make good use of the range of learning opportunities available within these sites. Mobile technology presents the opportunity to support educational visits by providing both location-based information and guidance through this information based on the visitor's interests and needs.

CAERUS is a working implementation of a complete context aware educational resource system for outdoor use. Location-based multimedia content and activities are presented to visitors through Pocket PC handheld computers with GPS capability. The visitor can view his or her location on the map-based interface (Figure 1) and is presented automatically with audio content upon entering a region of interest. Visitors can then select to view additional multimedia content for that particular location, capture their observations or continue with their exploration or tour. Administration of location-based content is accomplished through the CAERUS desktop application (Figure 2). Maps in any image format can be imported into the desktop application and calibrated with the assistance of the GPS-enabled handheld application. Once calibrated, the curator can divide the map up into regions, which correspond to physical areas within the site. Each region may be associated with one or more themes. Themes provide a specific perspective (such as "history" or "environment") on a multifaceted artefact or exhibit and can be used to group media such as text descriptions, audio, video and HTML. The system supports both free exploration based on a selected theme and 'guided' tours, where the next region of interest is suggested to the learner. Figure 3 illustrates the handheld application interface for a guided tour. A standard synchronisation procedure is used to transfer information between the desktop and handheld applications.

Design Methodology

The main aim in the design and development of CAERUS was to produce a system that could be applied in both tourism and education contexts. In addition to providing an engaging end user experience, a key requirement was that individual sites be able to manage location-based information and scenarios themselves and transfer this information to the handhelds efficiently.

Requirements for the design of the handheld CAERUS application were solicited through a questionnaire and focus group consisting of 8 regular visitors to the University of Birmingham's Winterbourne Botanic Garden. All participants were willing to trial a location-based handheld application but only if it 'just worked', indicating a low tolerance for technology failure. Specific design challenges from the perspectives of designer, implementer and user are described more fully in [START_REF] Naismith | Context-Sensitive Information Delivery to Visitors in a Botanic Garden[END_REF].

A preliminary user trial was conducted with a group of six participants, primarily to assess the usability of the handheld application. An issue that arose from this user trial was, again, a very low tolerance for technology failure. Audio content was preferred due to the rich visual nature of the botanic garden, echoing the findings of [START_REF] Oppermann | A Nomadic Information System for Adaptive Exhibition Guidance[END_REF]. Participants stressed the requirement for the audio to be very high quality and specifically relevant to what they were seeing.

Evaluation

Fourteen visitors to the Winterbourne Botanic Garden participated in a trial of the CAERUS Handheld System in May 2005. The trial consisted of four sessions and was conducted on two separate days a week apart. A planned activity was designated for each session and all participants within the session performed the same activity.

Table 1 describes the organisation of participants in the trial. Trial participants gathered in a central meeting space for a scripted overview and demonstration of the CAERUS handheld application. At this time, they were also asked to give a short statement of their knowledge of the garden. The appropriate option for the particular session was selected from the title screen (Figure 4), and then the trial participants were free to wander around the garden and use CAERUS as they wished. Informal observations were made while the participants were in the garden. Participants were instructed to return to the central meeting space when they were satisfied they had experienced the full functionality of the system. A short questionnaire was then administered, followed by a semistructured interview on their experiences.

Figure 4: CAERUS Handheld Title Screen

The main objectives of the trial were to:

• Assess general usability of the system.

• Assess how the different modes (theme, tour) affect user behaviour and ability to navigate around the garden. • Assess desirability of the system amongst different user groups.

• Assess desirability of different types of content amongst different user groups.

• Gather evidence for learning.

Equipment

Three handheld devices were used during the trial, all running the Pocket PC 2003 operating system. Two of the handheld devices were Mio 168 DigiWalker models with integrated GPS. The other handheld device was an HP iPAQ 5500 series with a Navman GPS 3300 in an expansion sleeve. The CAERUS handheld application was preloaded on all devices.

Except for Session 2, each participant was loaned a handheld device and earbud headphones for individual use. In Session 2, there were two pairs and one individual. The pairs in Session 2 opted not to use the headphones.

Results

The trial participants covered a range of demographic groups. Table 2 shows a breakdown of the trial participants by sex, age, experience of the garden and handheld device ownership. Trial participants spent between 30 and 45 minutes in the garden. Trial participants were asked to rate a series of statements on a five-point Likert scale. Table shows the mean and standard deviation of the response to each item, in the range from 1 (Strongly Disagree) to 5 (Strongly Agree). A one sample t-test was performed on each mean, with 3 (Neither Agree nor Disagree) as the constant value. Five statements show a significant difference from 'Neither Agree nor Disagree' (P < 0.05):

• CAERUS was easy to learn (a)

• It was not difficult to manipulate the push button interface (c) • Participants did not feel like they were in control of CAERUS (d) • Participants did not feel self conscious using CAERUS (h) • Participants would recommend CAERUS to other visitors (k) Comparisons between the group of participants over 50 and the group of participants under 50, however, showed a significant difference of opinion for the following statements:

• Using CAERUS does not require much training (a) -older participants slightly disagreed (mean response 2.8), while younger participants agreed (mean response 4.0). • It was easy at a glance to see what the options were for each screen (b) -older participants disagreed (mean response 2.5), while younger participants agreed (mean response 4.0).

Overall, the reaction to CAERUS was positive. Participants found the content provided during their visit to be both interesting and informative. As with the previous trial, audio was the preferred method of delivery. Several participants commented that the audio commentary was particularly clear. Participants described their experience with CAERUS as novel and liked the experience of looking at something while being talked to.

Problems with navigation and positioning, however, were paramount. GPS was described by the participants as slow and imprecise. Participants felt that too much mental effort was required to navigate and didn't want to have to look at a map to find interesting and relevant information. These problems were compounded by the fact that the handheld device screen was very difficult to see in bright sunlight.

Usability issues with the application itself were prevalent amongst the over 50 age group, with several participants citing a need for individual tuition (the application was demonstrated to the group). A common usability problem across age groups was that it was very easy to switch into 'demo' mode by touching the map area of the screen. In this mode, the GPS receiver is turned off so that the user can access information for other parts of the garden, without having to physically move. The demo mode is indicated to the user by a change in icon, but could be difficult to see, especially if it was done unintentionally. Participants can return to normal mode by clicking 'Find My Location' on the menu bar.

When asked what they would change, most participants requested enhanced positioning capability and information for more points in the garden and at a greater level of detail. While most participants said they would use CAERUS again in another location, a few of the older participants expressed dissatisfaction with the general concept and stated they would prefer a no-technology solution such as a paper map or leaflet.

Discussion

Comparison between different modes

All participants using the Tour mode made an initial effort to follow the suggested tour points in order, but all experienced difficulties with positioning and or navigation. Participants employed a number of different strategies to overcome these problems:

I started off using it trying to follow the guide, but then it just got infuriating, cause it pointing in the wrong direction, didn't go where I wanted to go and the GPS was inaccurate. So in the end I just forgot it and walked around. (male, 20-29, tour, first time visitor) I looked for the icons and I walked to them. (female, 20-29, tour, first time visitor) So I still used the suggested route, but I used the demo mode instead, towards the end. I roughly know where I am on the map, so I walked towards the point. (male, 20-29, tour, first time visitor)

The tour points consisted of both points within regions, and thus with attached content, and waypoints, with no attached content. Some visitors expected content to be available at all of the suggested points and were confused when no content appeared at these locations:

We tried to follow the tour; that was where we started having the difficulties. The tour sent us to places like go to the path towards the terrace, well what can you say about the path towards the terrace and it didn't say anything. (male, 60-69, tour, returning visitor)

The application didn't have a significant impact on the movement of the participants using the Theme mode. These participants were more likely to follow the natural paths in the garden, and wander between regions based on what visual sights piqued their interest.

Interestingly, several Theme participants requested greater guidance:

If you suggest to me you should go this way or that way and see this plant, that would be helpful. I would like to follow it. (female, 30-39, theme, first time visitor)

Navigating in information space

CAERUS requires visitors to navigate simultaneously through both physical and information space. A variety of factors impeded this process for trial participants including a lack of labelling both on the digital map and in the garden, a static map that didn't respond to changes in the user's orientation, difficulty seeing an overview of the garden on the handheld device and inconsistent performance of the GPS receiver.

Several participants used physical movement to verify they were navigating properly within the information space. This ranged from standing still while rotating the handheld device to match the visual surroundings to repeatedly walking back and forth along a particular path in the garden.

The participants felt that significant mental effort was required to use the application, which correspondingly led to a large amount of 'heads-down' interaction [START_REF] Hsi | A study of user experiences mediated by nomadic web content in a museum[END_REF]. The use of the handheld application was far from seamlessly integrated with the visitor experience:

It's not a physical experience; it's still attached to a device. (female, 30-39, theme, first time visitor)

Participants suggested a range of navigational aids to facilitate this process. These included simple solutions such as increased labelling, providing an accompanying map on a paper leaflet and an overview wall chart map available at the garden entrance. Technical solutions included enhanced positioning, displaying an arrow indicating the user's current direction of travel and automatically orienting the map to the user's current direction.

Evidence for learning

This trial did not attempt to measure learning against on a predetermined set of outcomes. Measuring the free-choice learning that occurs in informal settings is difficult for a number of reasons. Visitors come in with a range of prior knowledge, interests and motivations and continually interact with the physical and sociocultural settings in unique ways [START_REF] Falk | Learning from Museums: Visitor Experiences and the Making of Meaning[END_REF].

After their experience in the garden, however, participants were able to cite specific examples of things they had seen or heard:

The bit about the metasequoias, the history of the trees down there, and also a bit more about the history of the house. (male, 20-29, theme, returning visitor) I might've heard about the petal garden, but the shapes of the petals, I didn't know that.

(female, 60-69, tour, returning visitor)

The two on the balcony the two [wisterias], one goes clockwise and the other goes anticlockwise. Little things like that stick in your head. (female, 20-29, tour, first time visitor)

Participants also reported increased knowledge of the layout and organisation of the garden:

I worked here and I didn't know where the petal garden was. (male, 60-69, tour, returning visitor)

The garden is larger than I thought. I went down there and there's a natural path down there that isn't actually part of the garden, but you can walk along it to explore. (male, 20-29, tour, first time visitor)

CAERUS also prompted at least one participant to explore further:

I did look at some of the other information and I did actually try to find some of the trees as well. Just out of interest. (male, 20-29, tour, first time visitor)

Perhaps the best evidence for learning is that fact that most of the participants expressed a strong desire for more information, in multiple media formats:

I was just saying on the way back that although I didn't particularly want to listen to it at first, cause I thought I knew it anyway, it was so interesting and it could've been longer, even twice as long would've been fine. (male, 60-69, tour, returning visitor) I want to know more about the rose collection. (female, 30-39, theme, first time visitor)

You really need [more] photographs as well to make it a good experience. Something in blossom now will not have blossom later. (male, 20-29, tour, returning visitor)

Conclusion

CAERUS uses mobile technology to support visitors to outdoor tourist sites and educational centres by providing location-based information and guidance. Visitors using the CAERUS Handheld application on a trial basis reported high satisfaction in receiving location-based audio content and reported the use of CAERUS Handheld to be a novel and informative experience. A statistically significant difference in opinion was observed between older and younger visitors as to the amount of training required to use the application and how easy it was to see what the options were at a glance.

Significant mental effort was required for participants to navigate successfully through both physical and information space, leading to heads-down participation and detracting from the rich visual environment of the garden. Participants experienced particular frustration trying to use the Tour mode functionality, while those using the Theme mode expressed a desire for further guidance. This suggests that a rethinking of the Tour mode implementation is necessary, in conjunction with an investigation of both technical and nontechnical navigational aids.

While the trial did not seek to comprehensively evaluate participant learning, participants cited several examples of things they had seen or heard that were of interest to them. They also showed a generalised increase in their knowledge of the layout of the garden and a strong desire to obtain more detailed information in multiple media formats.

6.

Figure 1 :

 1 Figure 1: CAERUS Handheld Interface (Theme Mode)

Figure 2 :

 2 Figure 2: CAERUS Desktop Interface

Table 1 : Trial Organisation

 1

		Day 1	Day 2	Total
		Session	Session	Session	Session
		1	2	3	4
		(Theme)	(Tour)	(Tour)	(Theme)
	Number of Participants	3	5	3	3	14

Table 2 : Trial Participant Demographics

 2

	Sex	Male	8
		Female	6
	Age	20-29	5
		30-39	3
		40-49	0
		50-59	1
		60-69	3
		70-79	2
	Experience of	First Time Visitor	5
	Garden	Returning Visitor	9
	Handheld Device	Own a Handheld	4
	Ownership	Device
		Do not own a	10
		Handheld Device

Table 3 : Mean and Standard Deviation of Responses to a 5 point Likert Scale

 3 Test was used to compare the responses between groups. Comparisons of First Time Visitors versus Returning Visitors, Handheld Device Owners versus Handheld Device Non-Owners, Theme Participants versus Tour Participants and Male versus Female did not show any significant differences of opinion.

	Statement	Mean	SD	N
	a. Using CAERUS does	3.55*	0.69	11
	not require much
	training.
	b. It was easy at a	3.31	1.03	13
	glance to see what the
	options were for each
	screen.
	c. It was difficult to	2.15*	1.14	13
	select the option I
	wanted with the touch
	screen.
	d. I felt that I was in	2.46*	0.78	13
	control of CAERUS.
	e. CAERUS responded	3.50	1.22	14
	too slowly.
	f. I found it difficult to	2.46	1.27	13
	read the text on the
	screen.
	g. CAERUS helped me	2.71	1.20	14
	to navigate around the
	garden.
	h. I felt self conscious	1.93*	1.07	14
	using CAERUS.
	i. The way that	3.50	0.94	14
	CAERUS presented
	information was clear
	and understandable.
	j. It was difficult for me	3.79	1.37	14
	to determine where I
	was in the garden.
	k. I would recommend	3.57*	0.94	14
	CAERUS to other
	visitors.
	Starred items are significant at P < 0.05
	The Mann Whitney U

Acknowledgements

The design and development of CAERUS was supported by funding from Microsoft UK Limited and the Birmingham City Council to The Centre for Educational Technology and Distance Learning (CETADL) at The University of Birmingham, UK.

7.


IS SYNCHRONOUS COMPUTER MEDIATED COLLABORATIVE PROBLEM-SOLVING 'JUSTIFIED' ONLY WHEN BY DISTANCE? TEACHERS' POINT OF VIEWS AND INTERVENTIONS WITH CO-LOCATED GROUPS, DURING EVERY DAY CLASS ACTIVITIES

Is synchronous computer mediated collaborative problem-solving "justified" only when by distance? Teachers' point of views and interventions with co-located groups, during every day class activities

Argyroula Petrou, Angelique Dimitrakopoulou

INTRODUCTION

Is synchronous computer mediated collaborative problem solving a valuable and worthwhile activity for co-present collaborators? Could teachers accept to use it? Is it possible in the class time constraints? At which moment of their teaching do they estimate, that such an activity is worthwhile? Is it possible to apply it with usual problem solving activities?

Up to the present, most of the synchronous computer mediated collaborative problem-solving studies have concentrated on students' learning processes, pointing to the success with which it can be used to enhanced learning in educations settings [START_REF] Constantino-Gonzalez | Coaching Web-based Collaborative Learning based on Problem Solution Differences and Participation[END_REF][START_REF] Wu | Scaffolding group learning in a Collaborative Networked Environment[END_REF]. The teachers' role has been much less often studied, and when it is, is mostly for experimental purposes [START_REF] Lund | Teachers' collaborative interpretations of students' computer-mediated collaborative problem-solving interactions[END_REF] and not for exploring real school and class conditions. Therefore, an important aspect that needs more research is the challenges of tutoring in synchronous computer mediated collaborative problem-solving applied in real school environments.

PURPOSE OF THE RESEARCH

Until now, most of the studies on the teachers' role have been focused on networked computer supported collaborative learning scenarios: asynchronous tutoring, where the teacher studies the students' interactions and then intervenes at a distance across the network in order to help them [START_REF] Lipponen | The Challenges for Computer Supported Collaborative Learning in Elementary and Secondary Level Finnish Perspectives[END_REF], or synchronous tutoring, where the teacher observes (at a distance) the students' interaction in real-time, and 1 B. Wasson, S. Ludvigsen, & U. Hoppe,(eds.), Designing for Change, 1-6. © 2003 Kluwer Academic Publishers. Printed in the Netherlands.

intervenes to help them [START_REF] Lakkala | Approaches for analysing tutor's role in a networked inquiry discourse[END_REF][START_REF] Baker | Interactions épistémiques médiatisées par ordinateur pour l'apprentissage des sciences : bilan de recherches[END_REF]. In both cases, the teachers are not in the same room with the students. Besides, the systems that have been used in these studies, either support collaborative learning through a particular collaborative task, like CSILE [START_REF] Lipponen | The Challenges for Computer Supported Collaborative Learning in Elementary and Secondary Level Finnish Perspectives[END_REF], and FLE [START_REF] Lakkala | Approaches for analysing tutor's role in a networked inquiry discourse[END_REF], or they are domain independent but conversation-based, like CONNECT [START_REF] Baker | Interactions épistémiques médiatisées par ordinateur pour l'apprentissage des sciences : bilan de recherches[END_REF].

The present research aims at exploring synchronous computer mediated collaborative problem solving in real school context, with collocated students, in every day practice. How valuable does this approach appear to schoolteachers? "When" and "for what reasons" do teachers intervene, by what "means" and to whom do they address their interventions? What kind of interventions do they make during on-line activity and what during off-line debriefing sessions? Which are their functional roles when working on this mode? Which moments of the teaching process do they consider the time consumed is counterbalanced by its effectiveness? What tools do they need so as to apply on-line and/or off-line students' diagnosis in an easier way? This paper, independently from the effectiveness of collaborative learning, aims at exploring how valuable this approach may be for teachers. It presents a case study, that took place in a real school environment, where all participants, teacher and students, are located in one classroom, working on different computers, with typical problem-solving activities, (usually students worked in groups of two in front of the same computer). They used systems that allow synchronous collaborative learning, are easy to use, easy to get and are domain independent. With this approach it is possible for students to collaborate with almost any software they use in every day practice.

The working hypothesis underlying the present research is that teachers, (supported with specific tools), could develop a few new teaching strategies, without being imposed to change dramatically their practices immediately.

TECHNOLOGICAL ENVIRONMENT

The approach uses Windows Netmeeting, that allows members of one team to exchange messages, providing chat history, and to use any program in common (in a shared work-space) and Netsupport School that allows the teacher to inspect or share multiple students' screens from his computer. In this way, the most basic level of support a system might offer is assured, making the students and the teacher aware of the participants' messages and providing a shared workspace.

EXPERIMENTAL CONDITIONS

The participants were two teachers (Teacher1 and Teacher2), ten sixteen-year old students, from two different classes (five from each class). Neither teacher had previous experience with computer supported collaborative learning, but Teacher2 is a researcher and has worked on improving teaching through computer use. The teachers were not provided any initial instruction on collaborative learning and best practices. After the experimental sessions, an interview took place with each one separately. Each teacher had five students (one group of two and one group of three). The teacher placed students into mixed ability groups. The members of each group worked on their own computers, which were not located in the immediate vicinity of the class. Before starting, the students had a short lesson (20 minutes) on how to use NetMeeting.

Students worked on two activities (simple problem solving) from the lesson Computers' Programming, during four instructive hours (4 * 45 minutes) each class. The activities were not designed for the purpose of the study. They were chosen by the teacher, the students would do these activities anyway. For each activity, one common program (written in Pascal) was required from each team, for example "write a Pascal program that prints minimum, maximum and average after reading the marks of your classmates". So, the shared workspace was the environment of Turbo Pascal. At the first activity, it was additionally asked from students to answer the question: "can you find how many students were above the average without using arrays?" So, in this case, the final product was a collectively written text and the shared workspace was a Word document.

ANALYSIS

Analysis approach and research questions

Concerning the data, transcripts from (a) chat history between students and between students and teacher, (b) data from video * of the actions within the shared workspaces and the teacher's screen and (c) camera recording (spoken dialogue between teacher and students) were linked and merged. Thus, a single transcription file was produced, respecting the chronological order of events, containing the teacher's interventions (verbal and/or written) as well as students' dialogues and actions. This unified file served as the base for analysis, for each team (Excerpt 1).

The analysis is separated into the two great categories of teachers' interventions, according to the "moment of time" that they have taken place:

(1)

On-line interventions: teacher's interventions during the lesson while they observe students' interactions (dialogues and actions at the common workspace). (2)

Off-line interventions: teacher's interventions, during the next course session, after studying the unified file of data provided to them by the researcher. Usually, the teachers' interventions are studied, by assuming the intention of teachers messages or verbal expressions, attributing 'functional roles' (Vosniadou et al. 1999) or analyzing "question types and statement types" (Hmelo-Silver, 2002) that correspond to 'how teachers intervene' and lead to the discussion on the quality of teachers interventions, their strategies, and their approach. This kind of analysis seems to distinguish teachers' interventions from students' interactions, and often take place independently.

CORIOscan Select, a computer to video converter was used, to register the students' actions at the shared workspace, as well as the teacher's

In the present study, we tried to identify: A) (a) "when, and for what reason" the teachers' intervened, through previous examining and analysing students' messages and actions in the shared space. This was linked with the identification of (b) "How, with what means (verbal or written messages)" they intervened, as well as, (c) "to whom they addressed their interventions", whether to a specific group or to the whole class. Then, (B) we analysed, the way teachers intervened, by assuming the specific functional role of each intervention. Each intervention, given a specific cause, may include more than one message or verbal utterances by teachers. So, if during the conversation concerning a specific topic the teacher changes role, then we consider it as a new intervention. Referring to spoken dialogue during teachers' offline interventions in a debriefing session, the unit of analysis was teachers' 'utterances'.

Analysis of On-Line Teachers' Interventions

When does a teacher intervene?

Anlysis of teacher's messages and/or verbal utterances show that teachers intervene in the following general cases: A) Teachers intervene, by themselves, after examining the short previous history of each group interaction (teacher-requested interventions, Table 1) when: a) they have identified an error or a misconception from the students' actions (e.g. a part of the program in the shared workspace) or from their group messages, and b) they have identified non-appropriate collaboration modes. In some cases they seem to have studied the student's actions in the shared workspace (eg. identifying an 'error') while in others the chat history of the groups (e.g. revealing a misconception). B) Teachers intervene after students' request via messages (student-requested interventions, Table 1) where, a) students ask for help (related to the content or to a merely technical problem), or b) students need to inform teachers (e.g. that the task is completed). C) Teachers intervene by themselves, without examining any previous group interaction, for reasons of management of the whole class. Analysis of the data revealed that the functional roles of teachers' interventions could be divided in three main categories. Teachers act as: A)"providers of information related to the subject matter to be taught", B)"managers of interaction" and, C)"managers of the course process".

At Table 1, the following information is presented: who has initialised the intervention (student or teachers), what is the reason for each intervention (the 'when'), whether it results from actions' or messages' analysis, and which functional role the teacher adapted in each case. Table 1 does not compare the teachers' interventions but it is mainly an overview of the later. As far as teachers' interventions as managers of the course process are concerned, the reason of intervention had not to do with the specific solution or dialogue of groups, so they are not reported by the table, given their minor importance. Teachers intervened as managers of the whole process by themselves or after a request by the students when (a) there were technical problems due to the new approach, b) it was needed to do procedural comments, or c) off-task comments). In these cases, there were messages addressed to the whole class, all of them oral. Excerpt 1 from the transcription file (translated from original Greek).

As concluded from Table 1: A) Teachers intervene by themselves as providers of information concerning the subject matter to be taught mostly when they identify a conceptual or procedural emerging difficulty, analysing the actions of the members of a group or identifying possible misconceptions from their dialogue. They act as managers of interactions when they have identified difficulties during problem solving or non-appropriate collaboration. B) Students asked from teachers to intervene either by asking for help or just informing (e.g. that the task is completed). Students may ask for help under different conditions: a member of the group addresses a question directly to the teacher without discussing with his/her partner, or after a common decision if they are in an impasse, etc. C) Both teachers mostly intervene in order to provide information concerning the subject matter to be taught (especially Teacher 1), while there were cases when a more suitable intervention should be needed. For instance, a student who asks for help concerning the subject matter directly to the teacher without previous discussion with its collaborator should obtain an intervention from the teacher which would incite a group discussion on the question. Teacher1 explained during the interview, that he acted like this because "that is how I was used to working until now, since I didn't have the possibility to become familiar with the processes where the students collaborate". Teacher2, who acted more as a manager of interaction than Teacher 1, had a totally different opinion: "…these are activities that must be completed. You must get them started. So you leave them a period of time and then you intervene. Also, we must have in mind that the students must learn certain things during the day or even the school year and we don't have unlimited time".

Teachers' interventions were addressed to a specific group and not to the whole class. Only 6,97% (6/86) of interventions have used the written messages as support. In general, it appeared clearly that most of the teachers' messages were verbal. During interviews, teachers have commented on this point, "typing messages is time consuming, almost double the time is needed". According to them that's the reason most of theirs messages were oral. The other reason is that "we are used to acting this way". In traditional classes with face-to-face collaboration, teachers' requested interventions result only from actions' analysis, either from the final common product, or from collaboration's snapshots during lessons. As far as students' requested interventions, teachers have no way of knowing under which circumstances the students requested for help (e.g. if they have not discuss the issue firstly with the rest of the group). During synchronous computer-mediated collaborative problem-solving, as we assume from Table 1, teachers can additionally detect misconceptions, not appropriate mode of collaboration and intervene accordingly.

Analysis of Off-line Teachers' interventions

After studying the transcription file with teacher's on-line interventions and students' dialogues and actions, the teacher intervened one or more days later. In order to analyse the teachers off-line interventions, we focus again on the motive of each teacher's intervention, analysing this time the data from camera recording. The conditions, under which the teacher made interventions off-line are presented in Table2 and Table 3. Analyses of the data revealed that the teachers adopt three different roles: A)"providers of information related to the subject matter to be taught", B)"commentator of collaboration that took place" and C)"commentator of students' knowledge concerning the subject matter to be taught. According to the role that the teacher adopted each time, he/she intervened in some of the following cases. In traditional classes with face-to-face collaboration, teachers usually intervene when they want to correct mistakes at the final product, to solve problems that were not solved due to lack of time and to ask students questions in order to test their knowledge. Apart from above cases, they intervene to: verify that the portion of the final product that had been written by one participant, without discussion, has been understood by the rest of the team; when he/she wants to verify that the students had understood a subject that had been discussed on-line; when there are misconceptions (after studying history of dialogues between students of each team) that were not discussed on-line. The last case is very significant because misconceptions (in programming at least) are more likely to be "resolved" if the teacher not only discusses the misconception during problem-solving but also using probing feedback and post-summarisation strategies to address them after the problemsolving phase has ended [START_REF] Pilkington | Analyzing Educational Dialogue Interaction: Towards Models that Support Learning[END_REF]. So teachers after studying the transcription file didn't solely focus on students' errors or on their final product (program) as they were used to, something that is consistent with the findings reported at [START_REF] Lund | Teachers' collaborative interpretations of students' computer-mediated collaborative problem-solving interactions[END_REF]. During this phase, in contrast with on-line, teachers intervened more on cases that maybe they were not used to. Probably, because they had the time to study the transcription file, unlike on-line.

Table 2. Conditions of Teacher's interventions off-line as a provider of information

Teachers' Points of View

During the interviews at the end of all sessions, teachers expressed their points of view on: A) How valuable does this approach appear to them? Teacher 1: "these opportunities are valuable to us. It was interesting to see how a specific team works, or what was the contribution of some students in a team". Teacher 2: "This approach gives you the possibility to inspect a specific team, while they work and collaborate, to detect misconceptions, in order to intervene. I like to reproduce in the classroom snapshots from the problem solving process, and discuss it, …either with the specific group of students or even with the whole class." "Usually, when I work with my students in the lab, I can't follow what they do, and so I have only the final program (product)". B) When during the teaching process do they consider it appropriate to apply? Teacher 1: "…Of course, I cannot apply it, all the time. This approach is valuable especially in cases where we have already taught a unit, and we need to see what our students haven't understood, what they have misunderstood". Teacher 2: " I can use it from time to time, when we work on basic concepts and procedures, that are central for the rest of the course during the year". C) What tools do they need so as to apply on-line and/or off-line students' diagnosis in an easier way? Both teachers noticed: "A log file with the dialogues and the actions that took place at the shared workspace in parallel for each team is needed", that is a possible linked presentation of dialogues and actions in the shared space. "The contribution of each student in the final product must be obvious, and anything that has been deleted in the common product must be cancelled", that is the history of students actions in the final product, in order to see more easily who has contributed. "Visualize the dialogue in a way, that the teacher is helped while he/she is watching the dialogues on-line but also afterwards during the analysis of the dialogues" that is a kind of threatened discussions.

DISCUSSION

The main purpose of the present study was to examine if synchronous computer mediated collaborative problem solving is valuable in every day practice with collocated students and teachers. The analysis showed that computer supported collaborative learning provides the teacher with some new opportunities, in spite of certain difficulties (such as time consumption). This is so because learners interact through messages, and this information is available to the teacher as a resource that can be used to assess the learning that has taken place. Additionally, a teacher can monitor the actions at the shared workspace during problem-solving. Viewing the details of a problem-solving interaction between students could elucidate students' puzzling behavior [START_REF] Lund | Teachers' collaborative interpretations of students' computer-mediated collaborative problem-solving interactions[END_REF]. Besides, making the learning process of a group explicit, the teacher can be aware of the students weak and strong points and thus be able to intervene and monitor the group more effectively using different strategies according to the situation (Daradoumis, Μarques, 2000). Diagnosis is a really hard activity for teachers, and if they have the opportunity to apply it, at least to a certain degree, we consider that it is significant both for teaching and learning.

Before this research implementation, our assumption was that eventually, this approach could be interesting for teachers, (especially after some practice), even though they hadn't any special instruction, neither on collaboration value, nor on teachers' effective roles under these conditions. The conclusion that we derived is that application was possible and that it had positive effects on teachers' strategies, even when it was applied under minimal conditions: typical school problems, minimum technological support, teachers without any instruction, in the frame of limited school type. Maybe teachers face the whole approach positively, in contrast with findings of other researches [START_REF] Lipponen | The Challenges for Computer Supported Collaborative Learning in Elementary and Secondary Level Finnish Perspectives[END_REF], because they are familiar with the usage of computers and because synchronous computer supported collaborative learning was an integrated part of the learning environment. With this new approach, students solved the problems that were going to solve, they "carried out the assigned tasks". The need for providing teachers with tools that analyse students' activity (both on content and collaboration) and presenting their actions and dialogues in a form that facilitate teachers' understanding, is apparent from our research.

We consider that the use of a networked environment for collaborative problem solving with co-present students, was legitimated. Eventually, such a minimal approach could be considered as a first step for teachers to explore more powerful approaches that the computer supported collaborative learning inspire. Moreover, such approaches applied to minimal conditions, which are not far away from current teachers practices, neither are they linked to ambitious objectives, are often considered as a first step for teachers' involvement to new educational practices with technologies [START_REF] Casey | Computing as Educational Innovation: A model of distributed expertise[END_REF][START_REF] Sandholtz | Teaching with technology: Creating student-centered classrooms[END_REF][START_REF] Baki | Preparing student teachers to use computers in mathematics classrooms through a long tem preservice course in Turkey[END_REF].

Argiro Petrou, Computer Science Teacher, PhD Student, Learning Technology and Educational Engineering Laboratory, Department of Education, University of the Aegean, Greece. petrou@rhodes.aegean.gr Angelique Dimitracopoulou, Associate Professor, Learning Technology and Educational Engineering Laboratory, Department of Education, University of the Aegean, Greece. adimitr@rhodes.aegean.gr

The reported research has been performed in the frame of the IST-School of Tomorrow Project IST-2000-25385 "ModellingSpace". The project is coordinated

  You have to write if first. S33.Teacher2 [orally in class]: Guys you have to put parenthesis at command readln. When we use the hooks; {Provider of Information, Teacherrequested intervention, Actions' analysis, Problem solution}. S34.User6 [orally in class]: when we have comments. S34.User3 [sent the message]: Sorry (and release the control of the common workspace). S36.User5: [(he took the control) typed]: deleted the variables i and x from the command var readln (mark); If vathmos > max….. S37.User6 [sent the message]: why you deleted i and x? S38.User5 [typed]: if grade>max then max:=grade else if vathmos<max then max: S39.Teacher2 [orally in class]:User6 asked something and you didn't answer. Why you deleted variables i and x from command var? You have to answer. {Manager of Interaction, Teacher-requested interaction, messages' analysis, No help supplied y a member} S40.User5 [orally in class]: Sorry, I think we didn't need these variables.

	S29.User3: [typed]: var count, i, x : integer;
	begin writeln ('Give the students' marks'); readln (mark}; mark>max
	S32.User5 [sent message]:

Table 1 .

 1 Conditions of on-line teacher's interventions as a provider of informationconcerning the subject matter (Pr.info) and as a manager of interaction (M.Int).

	Conditions

of On-line Teacher's Interventions as a Provider of Information related to the subject matter and as a Manager of Interaction

				Teacher 1	Teacher 2
		Source	Reason	Pr.Info	M.Int	Pr.Info	M.Int
		Actions'	Problem solution	26,47%	5,88%	25%	7,69%
		analysis		(9/34)	(2/34 )	(13/52)	(4/52)
			Misconceptions	11,76%	2,94%	7,69%	9,61%
				(4/34)	(1/34 )	(4/52)	(5/52)
			No help supplied			5,76%	9,61%
	Teacher-requested interventi ons	Messages' analysis	by a member No participation by a member Regulation of common work-		2,94% (1/34 )	(3/52) 1,92% (1/52 )	(5/52) 1,92% (1/52 ) 1,92% (1/52 )
			space access
			Monitoring group		5,88%		3,84%
			progress		(2/34 )		(2/52)
			Talking instead of				1,92%
			chatting				(1/52 )
		Messages	Asking for help	11,76%	11,76%	9,61%	1,92%
		(asking for	without previous	(4/34)	(4/34 )	(5/52)	(1/52 )
		help)	discussion
			Asking for help	11,76%			1,92%
	Student-		after impasse	(4/34)			(1/52 )
	solicited		Asking for help on	8,82%		1,92%	1,92%
	interventi		a "technical"	(3/34)		(1/52 )	(1/52 )
	ons		problem
			No help supplied				1,92%
			by a member				(1/52 )
		Messages	Informing			1,92%	1,92%
						(1/52 )	(1/52 )

Teacher's off-line interventions as a provider of information related to the subject matter

	Source	Reason	Teacher 1	Teacher 2
	Actions'	Activities that were not solved	5,88% (1/17)	0% (0/7)
	analysis	Different Solutions from the two teams	5,88% (1/17)	0% (0/7)
	Actions' and messages' analysis	Mistakes in the final product, not discussed on-line was shared by group members Verifying that a portion of final product	11,76% (2/17) 23,52% (4/17)	0% (0/7) 28,57% (2/7)
	Messages' analysis	Misconceptions a subject discussed on-line Verifying that students had understood	29,41% (5/17) 23,52% (4/17)	28,57% (2/7) 42,85% (3/7)

Table 3 .

 3 Teacher's interventions off-line as commentator

Teacher's interventions off-line as commentator of students' collaboration and knowledge Teacher 1 Teacher 2 Comments on the collaboration of each team

		50% (4/8)	37,5% (3/8)
	Comments on students' knowledge	50% (4/8)	62,5% (5/8)

by the University of the Aegean (GR) and participate the University of Patras (GR), the University of Mons-Hainaut (B), the New University of Lisbon (PT), the University of Angers (F) and SclumbergerSema (SP). We have to thank teachers and students of the 2 rd Technical High School of Rhodes, Greece.