Science and Technology Education Center

Tel-Aviv University - School of Education Knowledge Technology Laboratory

The project reported here is aimed at building a Virtual Knowledge Park as a site on the Internet, fostering interdisciplinary learning of science, technology, and human culture. The development of the Virtual Park requires a systemic approach in dealing with questions and devising solutions regarding four main areas: subject matter, the learning environment, learning processes, and technological features. The features of the first prototype of a wing in the Park are presented: its structure (i.e., exhibition, experimentation, and workshop areas, knowledge center and main general spaces), the activities allowed (e.g., activation of exhibits, cooperative on-line tasks); and future development and research lines.

Acknowledgment: The authors want to thank all members of the R&D team: Orly Lahav, who coordinates the project and has supplied significant input on the development process section; Dr. Gil Amit, Shaul Katzir and Jay Horowitz (research and development); Amichay Oren and Shuki Barbash (programming and network solutions) and design team. The project is supported by grants by the Israeli Ministry of Science and Arts (for the technological infrastructure and client development) and the Israeli Ministry of Education (for the modules on learning activities, wings and information center).

Computer networks are finally here and within reach. They have been around from the 60s, first as modest local university networks, and from the 70s as rapidly growing national and international networks (e.g., ARPANET, BITNET). For many years they served mainly the needs of specific populations and social organizations, e.g., the defense or scientific communities. But now Internet is available to serve (in principle) everyone, everywhere for a myriad of different interests and purposes. Costs (e.g., hardware, communication services) are no longer a serious obstacle. Massive support to electronic publishing, web-browsing and telecommunications (e.g., web-pages editors, friendly 2D and 3D graphic packages, sophisticated browsers, audio and video-conferencing software, faster communications infrastructure) facilitates the generation and delivery of huge amounts of information and the creation of innovative communication configurations. For us, educators, it is very clear at this point that it is our turn to play. However, though the technology is there we have yet to clarify what educational questions regarding its use are worth asking, and what educational implementations are worth to be developed.

The project reported in this paper resulted from these concerns, namely, from asking a series of questions regarding the educational use of web technology and developing ways to study and answer them. For a start, we felt that we should change our perspective in relating to the new communication technologies. As with all new technologies, our tendency is to try tointerpret them first in terms of known models. In the case of web technology, models frequently used are those of data and knowledge bases, or TV broadcasting. In these terms the web is perceived as an innovative way to bring the world into the classroom (or home), like bringing in a CD or tuning into a TV show. Regardless the quality of the input coming in from the world (e.g., from breathtaking images or sounds to boring trivia) the learning environment, on this perspective, is still the classroom and not the web. This means taking into account only half of the story by focusing on the way-in ignoring the way-out, and moreover, ignoring two-way and multiple-way interactions. Our project builds on alternative models for perceiving and using the web, one of our key premises being to take the student wherever he or she is working from (e.g., school, home, community center) into the world. The learning environment is now an expanded one, including remote work-sites, people in different locations to interact with, and working time that is not restricted by the school time-frame.

The questions we have chosen to deal relate to four main realms: the learning environment, the learning process, the technology, and the contents of learning. Correspondingly, the four main questions we focus on in our work are:

1. What real educational needs could be satisfied by learning environments that take full advantage of the features of the web technology?

2. What learning processes can be qualitatively supported by working within web-based learning environments?

3. What features of the web technology appear to be of significant value for teaching and learning?

4. How should content areas and topics be treated within web-based learning environments.

The Knowledge Technology Lab at the Tel-Aviv University is looking into these questions as part of the Knowmagine project. This project aims at developing a Virtual Knowledge Park for Science Technology and Culture on the Internet. In this paper we will elaborate first on the requisite features of a museum-like environment on the web; then we will describe the Virtual Park project, and finally we will present our research and development agenda.

Our work on the required features of a web-based learning environment began by considering alternative models of learning settings. Many models (which rely on non-web technologies) are at use in educational settings, e.g., the classic classroom model, group work model, or independent studies/personal project model. Other models were adopted in non-formal educational settings (e.g., museums, community centers, public libraries) to offer members or visitors varied kinds of educational activities (e.g., guided tours, short term projects, worksheets, special-interest-groups activities). Among all models, we found museum-like environments to be of particular interest and to have a high potential for adaptability to the new technology. Let us briefly review their salient characteristics.

Museums as Educational Sites

The word museum derives from the Greek word mouseion denoting the temple dedicated to the Muses, who represented Culture. In the third century BC it was the name of a cultural center which held art treasures, established by Ptolemaic II in Alexandria. The Museo of the Renaissance, much like its predecessors, functioned as a place where art treasures were housed, preserved and displayed, by and only for wealthy and distinguished people. It was in the 18th century with the onset of the Enlightenment and the revolutionary era that the nature of museums changed allowing general public access to their cultural treasures. The Louvre in Paris was the first to open exhibitions to the public, and similar initiatives followed in London and in the United States. Thus the main function of the modern museum came to be to educate the public by displaying the evolution and progress of knowledge. This new role of museums was also reflected in the design of its exhibition catalogs, which aimed at communicating with the museums visitor.

Today museums are widely viewed as educational sites (Ingle, 1990; Vallance 1995). The educational idea however that museums rely on, namely that of using the senses to gain knowledge about objects and phenomena, is an old one. Its value was acknowledged in the scientific revolution of the 17th century and Comenius used it as an instructional concept in developing his visual textbook for children. But what, besides looking at objects, reading texts or hearing explanations should the visitor be doing in the modern "educational museum"? It is now commonly accepted that for a more comprehensive perception of the object in display it more information resources an involving experiences are needed. That is to say, the exhibit should be displayed in context, accompanied by information units of various types (e.g., text, a model, illustrations, video clips) and even inviting some kind of active involvement. As a result of these insights a visitor-centered approach to museums evolved (Dor, 1988), based on the idea that visitors come by choice and will look to satisfy their particular needs. As she wanders around, looking here and there, the visitor builds her private curriculum (Vallance, 1995). Reflecting this novel approach to the functions of the museum, workshops for children were designed and exhibitions linked to the formal curriculum. More importantly, in the case of science and technology museums visitors were allowed to manipulate and activate exhibits.

Different approaches to the implementation of educational activities in museums have been developed. Some museums, for example, the London's Science Museum, have incorporated a separate educational unit. The unit generates educational materials (e.g., booklets, guidance, web pages or special workshops) which aim to extend and enrich the visitors' experience of the exhibits and displays. The La Villete in Paris is an example of a different approach. It is a knowledge center whose educational functions were considered in advance - through all stages of its design and construction. The Israeli Science Museums in Haifa and in Jerusalem share this concept, and they design their exhibitions according to educational objectives, allowing visitors to manipulate objects and offering workshops related to the exhibitions. The Israel Museum in Jerusalem has a special youth wing which mounts special educational exhibitions based on original exhibits and on materials from the museum's collections.

Research findings related to young museum visitors indicate that most of them prefer to visit a museum with friends. Moreover, in a museum workshop what teenagers enjoyed mostly was the social atmosphere that evolved there. Students like to touch objects and handle them: such tactile experience increases their motivation to learn more about the object (Ingle, 1990). In another study adults were asked how they would encourage people to visit a museum. Their answers suggested the importance of creating a balance between the excitement a museum should arouse and the relaxed atmosphere it should also create (Du Bery, 1991).

Based on reported experience of the above type, and on our own, we concluded that the learning process envisaged by museums with an explicit educational agenda should be student-centered, aiming at enhancing their curiosity and independent learning. In addition, we found dynamic exhibitions in museums' educational centers to be highly appropriate for implementing this visitor-centered concept. Though this concept has been generally accepted in some places in the world, and great efforts are invested in designing attractive exhibitions, yet a visit to a museum is not frequent activity for many students. It happens only once in a while and the visit lasts only for some hours. There is never enough time to examine the exhibits deeply or to get a full picture of a scientific phenomenon. In order to become a literate museum visitor more time per object and repeated visits are needed.

It is possible to offer some initial hints for the improvement of this situation. For instance, during a museum visit students should be able to wander around alone or in small groups, whenever they wish, under no pressure from time and place restrictions. While being mainly motivated by the visual dimension, they should be offered the possibility to get more information in a friendly and simple way. Moreover, they should be given the opportunities to manipulate objects, to experiment, and engage in collaborative activities, in ways that realize learning objectives. These features of the museum visit may help to create an appropriate mixture of leisure and knowledge acquisition, as well as a balance between social interaction and privacy during the learning process.

Although some of these requirements can be met to some extent in existing real museums, some others can not be easily implemented there. Let us consider, thus, possible ways of implementing museum-like learning environments by means of rapidly evolving communication network technology. It is worth to look, in this context, at what Cyberspace can contribute to the implementation of these ideas.

Cyberspace

In its earlier stages network technology focused on information transmission based on coding/decoding procedures (not very unlike the defining features of the telegraph and telephone technologies). The current stage, with computers being part of the communication process, is characterized not only by information transmission but by a holistic process of information handling: organizing, saving, retrieving and processing (Mitchell, 1995). E-mail, Listservs and conferencing are common network applications, improving interaction among people at remote locations. The social phenomenon resulting from the impact of network technology has been concisely termed as the "global village" effect. The term cyberspace was coined by Gibson (1984) to refer to this new kind of space comprising various kinds of knowledge representations and delivery modes. We would like to use this term in a broader sense: a digital environment free from physical attributes in which real world conventions are mingled with digital world conventions and through which human behaviors, feelings and activities might be enhanced (Mitchell, 1995).

Virtual Environments

Networked electronic databases have been in widespread use for several years now, today the term virtual libraries is used o refer to them. When does an electronic database turn into a virtual environment? The virtuality of the sites established on the Internet is based on the concept of going inside a place that has no physical boundaries and exists in the form of bits and bytes. This place may be called a library without walls and a book without pages, or a bitstore as the digital bookstore (Mitchell, 1995). This is an environment were real and virtual concepts are combined. Consider for example the "Expo WWW Exhibit Organization" on the Internet: here the developers use metaphors of real-life notions, e.g., tickets office, shuttle bus, post office, museum shop. Nevertheless, being a digital environment, the Expo site offers new opportunities which differ from those offered by the real-life museum: visits are possible from any place at any time; browsing and wandering around guided by the visitors' own interest are allowed; visitors can stay as long as they wish, come again as many times as they like, and communicate to other visitors and the site owners their thoughts and feelings about the exhibition.

Virtual environments in Cyberspace are designed according to digital rules and not according to physical rules. When rooms, houses, or walls as entities (resembling real-life objects) are included in a digital world they should play a different role from the one they do in real buildings. In avirtual environment they should not function as barriers but merely as a graphical representation of object or content classifications . In a virtual environment we might penetrate walls or be teleported from one place to another instantaneously instead of having to move along pre-defined paths. Walkways become logical entities showing logical links between knowledge entities and not constraining paths.

A virtual environment should create an immersion effect. Examination of the literature dealing with virtuality (e.g., Reingold, 1991, Heim, 1993) indicates that immersion of the participant in the environment is crucial. This immersion effect is achieved primarily by visual and audio stimuli and by giving the user a role to play. By this a world is created which is real in effect but not in fact (Heim, 1993). This is similar to the perceptual, psychological and emotional effect of reading a book. The immersion effect causes the reader to see heroes in a story not as literary creations nor as semiotic constructs, but as human beings (Ryan, 1994). Neither of the immersion features yet part of most virtual museums on the Internet. Technology does not as yet enable rapid display of visual information and smooth transmission of audio items which are essential for creating the reality immersion effect (although these technologies are rapidly evolving). Likewise no role playing is involved in most of the so-called virtual museums. In this respect virtual museums should exploit more of the defining characteristics of MUSE environments (Oren, 1995).

A MUSE (Multi User Simulated Environment) is a text-based virtual environment managed on the net as a data base of cyber-rooms. Each room contains a textual description of a place or a situation in which different objects and participants are involved. Users may log into a MUSE, explore the environment, examine the objects, communicate with others who are logged in at the same time, and might even create new rooms. Well known in the educational community are the MicroMuse (Kort, 1994 - through <telnet chezmoto.ai.mit.edu 4201>) and Oceana (through <telnet oceana.sdsc.edu 4201>). Though most of them are textual environments, a MUSE might cause immersion due to three key features: (a) the environment is based on a plot which uses real-life metaphors; (b) the visitor enters performing a role of her choice for taking part in the plot, and (c) social interaction is a crucial component of visiting and acting within these environments.

More sites referred to as virtual museums emerge on the Internet daily. They display more and more pictures, nicer graphic designs (fonts, colors, symbols, icons etc.) and more information items. But are we satisfied with the virtuality of these sites? Most of these sites advertise real museums (not including galleries opened by individual artists to display their own work). The aim of these sites is mainly to inform us about the real museum and to attract our attention to its shows rather than to function as self-contained learning sites. Bearing in mind the pros and cons of real museums we assume that the features of a virtual museum, as described above, will motivate students to explore more profoundly objects and ideas on display, experiencecollaborativeskillsand acquire a positive attitude towards learning. But we should be aware that the realization of the educational potential of such an environment (e.g., promoting collaborative learning, motivating remote information search and retrieval) depends on its mindful planning (Harasim, 1993).

The Knowmagine project constitutes our attempt to translate the above presented reflections into a working version of a virtual networked learning environment: the Virtual Knowledge Park The guiding principles for the development of the Park relate to four main areas: content, learning processes, technology and methodology.

Content

The epistemological approach underlying the selection of the Parks content is the view of technology and the artificial world as extensions, as well as facilitators for the development, of human capabilities (McLuhan 1964; Olson 1994). Each content unit in the park is treated through integrating scientific and technological knowledge within a broadcultural (e.g., anthropological, philosophical, historical, social processes) milieu. The Park is organized in wings, or thematic units. Each wing is organized around an issue or event of critical importance in the development of the human culture, e.g., turning points in scientific understanding of the world, or discoveries or inventions that affected the life of individuals and societies. Although such a theme is always treated on all dimensions (namely science, technology, culture), particular wings have a leading conceptual entry point or key issue. Two examples currently under development are a wing on Galileo Galileo's work (conceptual entry point: scientific transformations), and a wing focusing on Gutenberg and the evolution of printing (conceptual entry point: technological transformations). Once in a wing, a systemic treatment of any given issue encompasses underlying scientific principles and processes, technological creation and artifacts, historical development (of a concept or a technology)¨ social or philosophical considerations (including conceptual transformations or even paradigm revolutions), and issues in other areas of human activity (e.g., music, literature, art) which are relevant to the main topic.

Learning Processes

The second issue we dealt with while defining the rationale of our project refers to the nature and quality of the learning processes within virtual environments. Our rationale for learning in the Park focuses on two main levels: the knowledge, skills, and processes to be acquired, and the quality of the learning process while interacting with other students or visitors.

The park offers a great amount of factual knowledge on different content areas. But besides fostering the acquisition of this knowledge we intend to support the students active participation in the construction of knowledge and her or his acquisition and application of various skills: scientific experimentation skills, technological design and problem solving skills, and information manipulation skills (e.g., retrieval, browsing, decomposition or recomposition).

A central concern in our project is to offer opportunities for this knowledge and those skills to be acquired through interaction with other students, by facilitating the simultaneous presence of students from remote locations in the virtual environment. This is a powerful means for supporting remote-collaborative work, through e.g., distribution of goals and responsibilities for accomplishing a task, elucidation and discussion of ideas and hypotheses, or application of alternative and complementary ways for solving a problem.

Technological Features

Technological features of the Park were defined as to correspond with cognitive and learning features considered in our rationale. During the development process we deal with substantial technology-related questions, e.g., finding an appropriate compromise between the desire to design a sophisticated 3D environment and the demands (e.g., reasonable response time) imposed by the on-line and simultaneous work of several students in distant locations; creating solutions for the interactions of (visually represented) personas present at any given time in the same location; integrating various action modes within the environment (e.g., wandering through 3D space, manipulating objects, or browsing through html pages and vrml views); integrating textual, audio and video communication among visitors.

In designing the Virtual Park the following issues were taken into consideration:

The creation of a virtual reality (VR)-like environment. The user interface of the Park enables the user to walk through a three-dimensional virtual environment and interact with exhibits and other users. At this stage we have decided to adopt only some of the features that characterize virtual reality systems. We have not, for instance, adopted commonly used input/output hardware accessories such as head-mounted displays. Two reasons support this decision: first, and more mundane, is the wish to keep the Park as widely accessible as possible to users at schools, home, or elsewhere (i.e., in terms of costs, computing facilities, maintenance). But the more important reason is the still poor state of the research regarding the educational and psychological implications of theuse of the nascent VR technologies.

Although running the museum at this stage demands high-graphic-performance hardware, the cost of such technology, today, is much less than HMDs, Booms or Caves. We believe that suitable graphics capabilities and computational performance will be common in the near future both in school and home PCs, and we have already begun working on a version of the Park's interface software for these platforms.

Distributed Approach. The Park is a distributed environment. The Parks interior, it's exhibits and user actions (such as movements, communications etc.) are distributed among the different systems which are part at any given time of the Park's net. Once a user enters the Park all the other users are immediately aware of his/her actions. Changes in the Park exhibits are also broadcasted to all users. It is possible to either distribute the exhibits themselves, or links to exhibits which reside on other machines (very much like how the WWW works).

Evolutionary Development. The Virtual Park is undergoing an evolutionary development, in response to rapidly changing demands from the Park and the technology. The Parks design emphasizes flexible design that enables both fast prototyping and reusability. Object Oriented Designprocedures are used to create and encapsulate several modules. The modules could be extended or replaced during the different stages of the development.

Methodological Considerations for the Development of the Virtual Park

From the methodological perspective the Virtual Park is a curricular project. Most well established curricular theory and development models (e.g., Taylor, 1950; Lewy, 1977) were formulated in the context of pre-computer curricular technologies (e.g., textbooks, audio-visual aids, building kits). It is obvious that the essentials of these theories are still valid and relevant regardless of changing technologies. But it is also obvious that the nature of the new computer and network technologies arouses the need for a redefinition of some components of existent models, and even for the formulation of new layers for these models. For example, the emergence of hypertext technology represented a shift in perspective (contrasting with the textbook-based approach) relating to the generation of learning materials. Essential features of curricular outcomes had to be redefined, e.g., the criteria for defining knowledge units (e.g., self-contained units vs. chained pieces in a hierarchy), organization and configuration of the representational structure (e.g., web vs. linear), learner support features (e.g., navigation tools and road maps vs. linear text organizers), or nature of knowledge-manipulation skills (e.g., browsing and information retrieval vs. linear access and search). Additional examples are the contribution of advanced technologies to the expansion of the repertoire of representational means at hand (e.g., text, animation, video, sound, virtual worlds), or to the creation of learning interactions (e.g., among learners, or between learners and unlimited knowledge sources) not limited by time and space constraints.

These and many other features of advanced information technologies, necessarily prompt a revision of curricular models in use as well as the definition of new models. The accumulated experience in the development of computer-based learning materials and environments only partially satisfies these requirements. When networks and virtual environments enter the educational scene, a further refinement and extension of existentmodels is required. Accordingly, a key component of our project is the definition of a process model for the development of a typical wing (the curricular building-block) in the Virtual Park. This process model will be described in detail in the next section of this paper.

This section describes the structure and development process of Knowmagine, a Virtual Knowledge Park for Science, Technology and Culture. For the first prototype of the Virtual Park we have developed a wing focusing on the scientific, technological and cultural aspects of Galileo Galileo's work, e.g., his scientific contributions, the role of technology and instruments (e.g., telescope) in the development of his theories, his controversy with the church and Aristotelian concepts. The wing is called "Andrea's wing", named after the scientists loyal student in the Bertold Brechts play about Galileo. Andrea, the student in the play, here represents the opportunityto access not only the masters science but also the teaching interactions between the two, and the human and cultural significance of the conflict between opposed conceptions and ideas.

The Virtual Park Structure

The Park was conceived as a modular assemblage, with the wing serving as its basic building block. There are five types of functional spaces in the Park. Two general spaces are accessible from all wings: the Main Lobby and the Knowledge Center. Three more spaces are defined locally for each wing: exhibition areas, exploration areas, and workshop.

Wandering through the Parks spaces can be done in two ways: by moving among the rooms or areas according to their spatial arrangement, or by means of an interface feature represented as a (virtual) device called the percolator. If the user is located in a particular wing, using the percolator allows immediate teleporting to any area in the Park.

General Spaces

In the main lobby assistance and information is supplied to the visitors in the form of navigation aids (e.g., a 3D map of the Park, or a set of visual menus), and information boards (e.g., about general public activities, schedule for the week, or new exhibits). As in real-world museums and centers, the Parks shop is also located in the main lobby. This is the place where students can acquire different kinds of souvenirs and materials. They may download written, audio and visual materials (e.g., a map, a song, a short animation), learning activities (e.g., a puzzle, an experiment kit), or a souvenir (e.g., a poster related to a current exhibit, signs for their room or classroom's door).

The Knowledge Center is an hyper-like electronic information web (Figure 1). A large number of information pages is interlinked, and linked to many different relevant locations on the world web. The information contained is of various kinds: text, sound, 2-D and 3-D (VRML) graphics, stills and animation. Access to the Center is allowed from everywhere in the Park: to a specific section if the user is looking for information while examining a particular object or exhibit, or to the Centers home page if no specific link is activated. A subsection of the Knowledge Center is the Education Services Center. It contains learning materials for teachers and students aiming at specific goals, (e.g., focus on a particular topic or set of skills), or type of activity (e.g., a guided tour, a treasure hunt) or curricular connections with regular school activities.

exhibition roomspublic areas

Wing Areas:

Each wing includes three types of areas: exhibition rooms, exploration rooms, and workshop. In the exhibition rooms the visitor can find, learn about, and manipulate 3-D exhibits. For example, in the Andrea wing exhibition rooms the student can find exhibits like Galileo's telescopes, pendulum, heliocentric models of the solar system, or books like Galileo's writings, the Bible, or Aristotelian writings (Figure 2). The objects can be inspected and manipulated. For example the telescope can be manipulated to watch the moon's surface as Galileo did, or a book can be opened - entering the section of the Knowledge Center where the texts and related information are stored.

In the exploration rooms scientific or technological experiments and activities can be carried out. For example, students can replicate Galileo's inclined plane experiments, but in a different setting and in collaborative ways. In this case the environment is a virtual playground (Figure 3), with slides (inclined plane) and swings (pendulum). Students present in the same space at the same time can (virtually) each go down on a different slide (of different length and slope), while sliding time and distance are being measured. Each student can see the others sliding, and all results are displayed on a board. The students can now analyze and interpret the results, and elaborate on their implications (e.g., regularities, hypotheses, predictions).

At the workshop the students meet for performing fairly complex collaborative learning activities. In our exemplar wing the planned activity is a role playing event centered on Galileo's trial and confrontation with the Inquisition. Students have to sign in two weeks in advance, choosing one of the ten characters participating in the event (e.g., Galileo, the Pope, the Inquisitor, Aristotle, Einstein). Each character has to prepare her or his presentation at the trial¨ using materials and documents contained in the Knowledge Center of the Park. A week before the trial, all presentations are delivered to all participants (via the network), so they can all consider their responses (Figure 4). On the day of the trial all participants meet in the (virtual) workshop room, and the trial proceeds as a video conference. Each participant gets a slot of time to deliver her or his presentation, followed by a discussion, and finally a verdict (here the public -other people connected and present in the trial- can participate and vote). One of the characters is the moderator of the discussion, her or his main role being to uphold the trials rules and make sure it proceeds orderly, from stage to stage.

Process Model for the Development of the Virtual Park

The process model consists of a set of layers (Figure 5), which from the bottom layer up represents also the temporal sequence for the development of a wing. For each layer were defined its main goal, required inputs, process of elaboration, expected outputs and staff involved.

The first is the Conceptual Layer. The aim here is to generate the conceptual infrastructure of the wing. This layer takes two inputs: the general learning objectives for the wing (e.g., knowledge, skills, linkage to other subjects), and information about the target population. The process at this stage consists in defining the learning objectives for the wing, and in gathering information and knowledge from varied sources (e.g., knowledge bases, experts) for building the required content base according to these objectives. This layer has three outputs. The first is the set of learning objectives (or sets, depending on the needs of different populations visiting the park). The second is a content matrix where content items are organized by categories (e.g., terms, concepts, facts, themes, scientific principles, technological principles, key actors and personalities, historic or cultural events). The third output is the concept web, where all content items in the matrix are rearranged in web-like configuration indicating relevant structural features (e.g., links among items, chunks or sub-sets according to definitional criteria, hierarchies). The team involved at this stage is the nuclear or leading team for the wing, with the occasional aid of experts in different content, didactic or technological areas (see example of a content matrix and web in Appendix A).

The second layer is the Representational Layer which translates the Conceptual layer into representational means within the virtual environment. The input here is the conceptual web from the first layer. The process consists in making decisions and creating design specifications about the form each content item will take (e.g., text, sound, video-clip, 3D exhibit, manipulable object). The output of this stage is the attachment of an additional dimension to the first layer's matrix and web, namely, the representational dimension. At this stage the nuclear development team is expanded toalso include the design person.

The third is the Didactic Layer whose inputs are the sets of learning goals (from the first layer) and the integrated Conceptual and Representational web (from the second layer). The process at this stage follows the curricular methodology commonly in use for the development of learning materials and environments, but adapted to fit two sets of requirements: those derived from the educational rationale of the Virtual Park, and those derived from the particular features andqualities of the computer network technology. The output at this stage is the detailed planning of learning activities and interactions according to the defined objectives and target populations. These activities cover a varied range of learning interactions as defined in our rationale (e.g., just wandering and watching, activation of exhibits, retrieval of information about exhibits, doing experiments or building tasks, taking part in a collaborative task, participating in a long-term group learning event). The programming team join the development team in this planning stage.

Fourth is the Implementation Layer whose input consists of all planning and design documents generated in previous layers. The process at this stage is a compound of methodologies characteristic of each sub-component, e.g., didactic writing, programming, 3D and 2D design, web-page composition. The output for this stage is the first experimental version of the wing, including the tri-dimensional space, the exhibits and their scripts, allowed activation, corresponding section of the knowledge center, and the first set of individual and collaborative learning activities for different goals and populations.

From this stage on the usual evaluation cycles are activated until the running version of the wing is delivered, namely, pilot run of the experimental version, revision in light of pilot conclusions, large-scale pilot and subsequent revision, delivery of running version and periodic upgrades.

The Virtual Knowledge Park project represents an attempt to explore new educational applications of computer-communication technology. The search for these potential applications was primarily guided by learning and cognitive considerations: we did not want to merely install the new technology in schools only because it is here, but to relate it to substantial learning needs and questions. This led us to the construction of the project rationale as an integration of theoretical approaches to learning (e.g., development of alternative learning settings, guided discovery, information manipulation processes, collaborative learning) with features of the new technologies (e.g., virtual spaces, multi-user communication activities, integration of different media, hypertext, the world wide web). Underlying the definition process of every component of the Park was the same question: how does it relate to our rationale and to our basic educational questions?

Our research and development agenda now takes us in several directions. The first is the transition from a lab prototype to a fully accessible site. A feature we are already incorporating for supporting this goal is the development of multilingual (Hebrew, English, Arabic) versions of the Park. In addition support for different hardware platforms in use at schools is currently under development.

Another direction relates to the implementation of the described model as a template for the further building of new wings by developers at our center, in schools and informal settings. An example is the development process of a new wing dealing with Gutenberg and the technological and social implications of the invention of the printing press (Figure 6).

Finally, we will devote considerable effort in studying substantial questions regarding the students work and learning within the Park, e.g., motivation, interaction with the environment and among students working at distant locations, acquisition of unique skills (e.g., browsing in the knowledge center, exploration of virtual objects), the Parks' activities as trigger for further learning, or transfer.

Virtual environments and network technology constitute interesting promises for the development of newer, richer and motivating alternative learning settings. We believe that a combined research and development effort, such as the one presented in this paper, will help us to discern the real educational value of these promises and their practical contribution to learning.