53k jpg 56k jpg
Classroom Infrastructure: Computer Bricks and Software Mortar
For the compelling forces that were listed in the last chapter to have any effect there must be a system architecture and an infrastructure to support the electronic educational environment. The switched on classroom is not a mere fantasy nor an artist's conception. It is a room with real and functional hardware. Before we can seriously consider the actual use of an electronic classroom, we must have an idea of the necessary capabilities and functions that must be implemented.
The electronic classroom can be constructed in many different ways with many types of architecture. Each facility built to date is different with more or less equipment, slower or faster computers, and bigger or smaller displays. No one can really define what an electronic classroom is or what it must have in it to be counted as an electronic classroom. However, in this chapter we will explore a number of aspects that help to support the electronic abilities listed in Chapter 3 and the educational objectives listed in Chapter 1. Moreover, we will try to understand what must go into the electronic classroom to support what it is supposed to do. We will look at the physical layout of the room, the computer workstations, the room displays, multimedia access, the local area network, and the wide area network and video conferencing systems.
4.1 Room Layout
It might seem that the arrangement of desks and workstations in the electronic classroom is an irrelevant aspect. However, room arrangement is extremely important because of the difficult mix of technology and people in the same space. In addition, the configuration of workstations and the location of the instructor directly influences the effectiveness of various types of interaction: lecture presentation, class discussion, and formation of small groups. The configuration of workstations and students may suggest the format of a lecture hall, a theater, a study hall, or a round table discussion.
Figure 4.1 shows four types of configurations of the electronic classroom. The first configuration is the rectangle. Workstations arranged in straight rows provide easy access and location of positions. It suggests a lecture format with a clearly defined front of the classroom. The second configuration of a semi-circle focuses on the front with even more of a suggestion of a theater format. The semi-circle is particularly useful for large classrooms.
The last two configurations have no clearly defined head of the classroom or podium. The conference table arrangement is ideal for small group interaction and the round table arrangement extends it to a number of small groups. The problem with the last two configurations is that when one needs to shift the focus to one presenter at the front of the classroom, a number of students have to turn around. Nevertheless, if one wants to break away from the focused lecture presentation and emphasize student interaction and collaboration, this may be the preferred configuration.
Movable configurations would be desirable for small classrooms in which one frequently shifts the focus of activities from the instructor to the students and back. If the logistics of movable workstations, cables, and connections can be overcome, students could reposition themselves into the optimal configuration as needed. This is an obvious advantage of the traditional classroom with movable desks and chairs. However, with laptop workstations and wireless networks, the switched on classroom will be able to achieve this level of versatility.
In any of these configurations, it is important to maintain clear lines of sight to the front of the classroom and among the students. For this reason, is it important that the workstation monitors be recessed low enough to be out of obstruction. If possible flat panel displays should be used.
Workstations provide the interface between the students and instructors and the electronic media. The allocation of workstations to the students and the instructors is one or the most important dimensions in the architecture of the electronic classroom. At one end of the continuum, some boast of classrooms in which only the instructor has a workstation that he or she uses to display lecture material, show videos, and run demonstrations. To be sure this is an enhancement over the traditional blackboard, overhead, and slide projector. But it provides access to the electronic material only for the instructor and enhances only his or her role as lecturer. The students may be entertained by this show, but their role as passive spectators has not changed from the traditional classroom. As argued earlier, students need to have their own workstations to provide personal input and display. Moreover, it is essential that each student have his or her own electronic workspace in the same way that each have their own desk space. The reason for this will become even more apparent when we consider the use of the computer network.
Near the other end of the continuum, there are many installations in which each student has a workstation but not the instructor. These rooms are most appropriately called "computer labs" rather than electronic classrooms. They are designed for independent student access to computing facilities and not for classroom or group activities. What is missing in the computer lab is a workstation for the instructor because in general there is no instructor. In the switched on classroom, the instructor can take on many different roles, but to do so he or she must also have access to the electronic materials. Consequently, for the architecture of the classroom to be complete, each student must have a workstation and the instructor must have at least one workstation and in some cases several to handle different educational activities simultaneously.
Many technical requirements could given for the workstations. A brief checklist
is shown in Table 4.1. However, a detailed list of specfications is neither appropriate for this treatment of the subject nor would such specifications be current for long. Let it sufficise to say that one should constantly aim for state-of-the art technology, reasonably priced, and popularly accepted in the marketplace. While some may argue that education can get along with older generation equipment that can be purchased second hand or received as donations, in reality such equipment and the attitude behind it only serves to frustrate the students and to de-value education. Second hand equipment has tended to be more of a curse than a blessing when support, maintenance, and repair are factored in. Furthermore, it sends the message to students and teachers that what they are doing is of secondary importance. Instead, we must remember that it will be the students in school today that will be using the systems of the future not the systems of the past. They must be given the best first. In the future it should be the school systems that donate their second hand computers to business and industry! More will be said about this at a later point.
Checklist for Educational Workstations
CPU fast enough for rapid rendering of complex graphics
Large memory and hard disk storage
Totally quiet with either no fan or located in a separate room
Medium for Input/Output:
Current medium of floppy disk and CD-ROM with access to a larger variety of medium and translators
High resolution color, at least 256 colors
Large enough to adequately display several windows
Enough contrast to be viewed in either normal room lighting or dimmed lighting
Recessed into the desk at approximately a 40 degree angle
Silent and durable keyboard
Mouse and/or touchscreen
Stereo output with earphones switchable to room speakers
If possible, a directional video camera
One question concerns the standardization of workstations versus the accommodation of a variety of workstations. Current electronic classrooms typically host only one type of workstation. This reduces the nightmare of incompatibilities in hardware and software that can crop up. These, of course, are installations in which the workstations are provided rather than classrooms where the students bring in their own laptop computers as workstations. The latter case may in a few years overtake the former as laptop and palmtop computers become more powerful and accessible. In spite of the proliferation of diverse hardware and software, there is an increasing movement in the computer industry both for cross platform standardization and for cross platform translators. While this may help to alleviate the problem with multiple types of computers in the electronic classroom in the near future, at present it is best to stick with uniformity.
4.3 Local Area Network
The computers in the classroom must communicate with each other. This is done through a local area network and one or more servers. The network provides for the transmission of information between the workstations and the server. The server is a computer with a large file storage capacity. Generally, for the students to access to server they must have an account name and a password. If possible, account names should be derivatives of the person's name such as "jsmith" for John Smith rather than "eng23" for the 23rd student in English 101.
The network software allows a system administrator to give read/write privileges to the account names. For example, the student may have read/write privileges to his or own directory and read only privileges to a directory containing the instructor's notes. The instructor, on the other hand, would have read/write privileges to the directory with the notes and may also have read/write privileges to all of the student directories. As suggested in Scenario 3 in the introduction to this section, the technical configurations of the network may be rather complicated and specific to a particular installation. However, the concept of spaces and communication across the network is not that complicated and should generalize across many systems.
Table 4.2 lists six types of storage areas needed in the switched on classroom. To start, each student as well as the instructor should be assigned a Personal Space accessible only by that person. The Personal Space could be used for anything that is not yet meant for others to see. For the instructor it could be notes in preparation, personal files, etc. For the students it could be work in progress, personal notes, etc. The important thing about this space is that it guarantees privacy.
The second space is for the instructor. The Instructor Space is for storing assignments, exams, notes, grades, feedback, and just about everything about the course that is not public. If there is only one instructor, the Instructor Space and the instructor's Personal Space are functionally the same. However, in many courses with different sections taught by different instructors or in courses with several teaching assistants, the Instructor Space should be accessible by all of the instructors and/or teaching assistants to provide course materials to them.
Student Spaces are areas where the instructor and each student can share files. It is a working area for each student containing files of exams, notes, assignments, and grades for that student. The instructor can write files to each student space and can read files that each student has recorded in this area. While the instructor can read and write to all of the student files, each student can read and write to only his or her specific area.
The Handout Space is an area that can be used to give students general access to class material. In general, the instructor would write a file to this area and then students would read that file. The Handout Space is essentially a one-way channel to the students. The Handout Space is used to provide assignments and other information to all students.
The Handin Space works in the reverse direction as the Handout Space. The students can write to the Handin Space but they cannot read or change any existing files that are stored there. When an assignment is complete, it can be written to the Handin Space where no one but the instructor can access it.
The Interact Space is an area that is open to everyone. It is used as a free area for passing any information to anyone. There is no network imposed privacy. Methods of encryption can be used but anyone can overwrite or delete a file. In a non-hostile, friendly environment, as should be the case in education, the Interact Space can be used for interactive group sessions and for collaborative interaction which will be discussed in a later chapter.
Finally, it should be noted that each computer has its own hard drive. If the computers are fixed in the classroom and are used by different students, they should not store anything on the computer's hard drive. It should be used only for system software and resident application programs. However, if the students own their own laptop computers that are brought into the classroom, they may use their own hard drives for their Personal Space.
Since files are stored on a server accessible across the network, students and instructors are not limited to any particular workstation or location. Students may sit in different locations in the classroom on any day. For that matter, if other workstations outside of the classroom are networked to the server, students can access materials outside of the classroom as if they were there.
File Areas and Read/Write Privileges
Instructor A Student
Own Read/Write Read/Write
Others --- ---
Instructor Space Read/Write ---
Student Spaces Read/Write
Handout Space Read/Write Read Only
Handin Space Read/Write Write Only
Interact Space Read/Write Read/Write
4.4 Wall Displays
So far we have focused on personal workstations rather than on group displays. However, for the electronic classroom to be a classroom it requires a group focal point as well as personal displays. In the traditional classroom this has been the blackboard or the projector screen. In the switched on classroom it is one or more large screen monitors or high resolution video projectors. The group display can be used by the instructor for the presentation of information during a lecture or more interestingly for displaying group results.
The wall display will have to be electronically switchable to project either the instructor's monitor, any of the student monitors, or any other video input. Figure 4.2 shows a schematic of two wall monitors connected to switching system. Switching should be simple for the instructor and should involve a one button operation or it should be computer controlled and programmable. The instructor should never have to fumble with the confusing buttons on one or more remote controls or instrument panels. Instead he or she should only have to select the source and the destination; and all other switching and compatability of signals should be automatic.
Wall displays must be large enough for the whole class to see clearly. For a moderate size classroom, they should be at least 4 x 6 foot. They must be located in the front of the classroom with a good line of sight for each student. They should be bright enough that it is not necessary to dim the lights substantially for them to be seen. Finally, their resolution should be at least as high as the workstation monitors in front of the students.
4.5 Multimedia Access
The electronic classroom must have extensive access to multimedia materials along with the ability to manipulate and display this information both proximally on the workstations and distally on the wall displays. Video tape, laserdisc, and broadcast television are being replaced with CD-ROM and MPEG compression. While more and more of this material is digital and can be transmitted across the network, other media still exists and may always exist. What is important is that in the switched on classroom the instructor and students be able to find and present this material in a seamless way. The start and stop time should be neglible. Each component, whether an image, an audio segment, or a video portion, should be integrated into the information flow in the classroom. This requires both sophisticated hardware and software.
It should also be emphasized again that while multimedia presentations by the instructor are an enhancement over previous traditional lectures, they are no guarantee that learning will be improved. There is no evidence that the pressure of the multimedia blitz will produce lasting impressions in the minds of the students. They may be captivated, impressed, and entertained; but if the material is not carefully mapped to the learning objectives and meaningfully linked to the knowledge structures in the course, it will be time wasted.
Multimedia educational materials should not be only in the control of the instructor. The students need to be personally empowered with the ability to search, explore, and study the multimedia materials on their own. In the hardcopy classroom, the students had personal access to textbooks and other printed material, but student exploration and study of films or demonstrations shown in class was generally out of the question. In the switched-on classroom, students should be able to explore, replay, and re-organize the multimedia materials themselves. Furthermore, many of their assignments may be the exploration and thematic re-structuring of materials into their presentation. The capabilities of search-ability, copy-ability, and link-ability can be used by the students to generate new types of course products.
4.6 Wide Area Network: Distal Teaching and Access
One of the most important features of the switched on classroom is not the network within the classroom but its connection to the network outside. First, the local area network is connected to the campus network and all of the servers and resources on the campus. This might include library resources, information resources, and computing resources. Second, the classroom is connected to the world by way of the Internet, the World Wide Web, and other networks for video conferencing. What gives power to the switched on classroom is the wealth of information that will be readily accessible in the classroom not only for the instructor to use but also for the students. Once the classroom has access to the network outside the classroom, the problem will not be the amount of information, but finding the information. One of the primary activities of both the instructor and the students in the switched on classroom will be finding the relevant information and creating the logical sequence that weaves the information together into a coherent story.
In addition to stored information, the network can bring in on-line guest speakers, interviews with experts, and interactive visits to distant sites. Compressed two-way video can be used bring in visiting lecturers from other locations. The class can interview leaders in the field and ask questions directly to the author of the textbook or to the originator of an idea. Alternatively, it is possible to take the impossible field trip to important locations across the country or even around the world. A virtual field trip to the San Diego zoo to participate in the birth of a tiger cub could be accomplished by a two-way compressed video system that allows the class to control camera angle and zoom. Requests and questions to the zoo keepers could be sent from the class on the monitor at the zoo. Although it would not be the same as actually being there, such a system would clearly open up virtual visits that otherwise would never be possible, even to visit a space station, an operating room, or even behind enemy lines in a battle.
The actual design and construction of an electronic classroom is a complicated task. While there are a no off-the-shelf designs yet, there are a number of prototype classrooms built for experimental purposes. These prototypes have helped to refine the objectives of the classroom and test the hardware solutions for achieving those objectives. Many classrooms have been underbuilt, helping to reveal the necessary functionality that was lacking. Other classrooms have been overbuilt revealing hardware options that may be under utilized or never used. Each generation of electronic classroom, hopefully, will built on the lessons learned through the previous generation.
This chapter has focused on the physical design and hardware of the electronic classroom. The obvious follow-on question is, "How do you use all of this technology?" The answer to this question comes in two parts. The first part requires a definition of the educational process and the tools of learning. The second requires a mapping of these processes and tools onto an educational software system. To this end Chapter 5 will define the gulf that needs to be crossed and Chapter 6 will begin to build the bridge.
Exercises and Projects
1. For computer technophile, write out specifications for an electronic classroom complete with workstations, server, and network.
2. Think of three different types of courses that could be hosted in an electronic classroom. Decide on the room layout that would be most appropriate for each.
3. Given the six spaces defined in Section 4.3, where would you locate the following files: Course Syllabus, List of Grades on Exam 1, Grade for Student 3, Note to the Instructor from Student 5, Instructor's Notes from Last Class, Instructor's Notes for Next Thursday, Joint Project of Student 6 and 10, Public Information about Students, Assignment Due Next Thursday.
[Table of Contents] [Chapter 3] [Chapter 5]