Figure 1. An Example of a Course Map and Topics Index
As an example of courseware development we describe simulations of computer networks which were developed as part of a course on distributed computer systems.
1. We have been using HyperCourseware to develop computer assisted learning material for many subject disciplines within the university (e.g., Engineering, Mathematics, Computing, Business Studies, Teaching, Food Sciences, etc) and also applying the same HyperCourseware principles to novel projects like an on-line Courseware Catalogue and an on-line Library Guide. This experience has enabled us to formulate and refine methods for enabling staff with very little computing experience to become closely involved with the processes of courseware development.
2. We continue to modify the HyperCourseware tools which we use extensively for courseware development. Our plans for the original Macintosh based HyperCourseware Management System include adapting the design in order to develop a common version for Macintosh, PC's and Unix platforms. Meanwhile, we have also built a 'HyperCourseware Starter Pack' (on Macintosh computers initially) which contains a miniature version of the original HyperCourseware Management System and a library of adaptable courseware templates. Versions of this starter pack have been inexpensively available to all educational institutions since November 1992.
Our experiences confirm our previous assertions which are that general-purpose hyper systems have immense educational potential and that this potential can be expanded and more readily realised within a framework like HyperCourseware which directs that potential specifically towards educational objectives.
The definitions are very flexible and allow authors to determine what constitutes a coherent collection of related topics for a particular piece of courseware, and what constitutes a coherent collection of related educational activities for each topic in a course. Educational activities for a topic might include some traditional ideas such as stating the objectives of the topic and the pre-requisite knowledge a user should have before embarking upon the topic; providing presentations, resources, assignments, sample solutions, and performing assessments, etc. An educational activity can be composed of any combination of primitive activities e.g., read a piece of text, look at a picture, listen to a sound, look at an animation (computer based or video based), play with a computer based interactive device (e.g., simulation), or follow some instructions to perform an assignment away from the computer.
2.1 Facilities within the HyperCourseware Starter Pack
A HyperCourseware Management System is an integrated collection of software tools and utilities. These tools and utilities enable authors to manage and manipulate courseware. The terms manage and manipulate are used to refer to the interleaved activities which authors perform such as constructing, structuring, editing, viewing, and navigating courses. A primary aim of such a system is to serve both novices and experts in the craft of courseware development. This means that unnecessary programming effort is minimised or eliminated wherever appropriate, thereby enabling authors to concentrate instead on the educationally interesting aspects of courseware development. It has been repeatedly demonstrated at South Bank that users with minimal computing knowledge can quickly learn to develop effective courseware using the HyperCourseware Starter Pack. It is now regarded as routine practice for courseware to be developed via student projects.
The HyperCourseware Starter Pack (for Apple Macintosh computers) contains the following tools and utilities :-
Topic Templates: an expandable set of educational activities which are provided as empty templates. The templates are HyperCard™ stacks so they totally adaptable; they are provided in a variety of styles and screen sizes and authors can either use them as they are or customise them as required. The library of templates includes Title pages, Objectives, Pre-requisites, and other orientation activities; Presentations; Assignments; Assessments - including multiple choice, multiple selection, true/false, gap fill, etc.
Mini Browser: this device enables authors to structure their collections of topics. It maps the hierarchical collection of topics onto a corresponding folder structure in the underlying operating system. The Mini Browser provides a basic kit for building course maps and generating topics indexes automatically. (see Figure 1.)
Applications Launcher: this device enables users to run other Macintosh applications from within a piece of courseware and to return to the courseware after finishing with a launched application. This facility in a primitive form is a built-in feature of HyperCard but in the HyperCourseware Starter Pack it is significantly upgraded to allow authors to make elaborate use of the facility without resorting to writing programming code. The importance of this facility cannot be overstated. Authors can develop extremely effective courseware by remaining within the capabilities of HyperCard but the possibilities are enormously enhanced if authors also exploit a diverse range of software applications e.g., specialised animation tools, spreadsheets, multimedia tools, etc. The applications launcher allows authors to integrate these other software applications into the HyperCourseware templates.
The courseware examples described here are chosen to illustrate a variety of approaches to developing dynamic and interactive activities. The ideas are all pragmatic i.e., they have all been exploited successfully by a small team devoting limited time to courseware development projects.
It is obvious to any experienced author that no single authoring system will ever be appropriate for all educational developments (despite the claims of several professional vendors), and therefore it is essential to have the capability of integrating activities developed using different tools. For example some courseware which SCALE developed had the aim of teaching mathematics teachers how to incorporate information technology into their teaching. The courseware deliberately incorporated several software applications i.e., MediaTracks™ to provide recorded movies of a spreadsheet being used to work on number patterns; HyperCard™ to provide a simulated spreadsheet with which users were directed through spreadsheet exercises; Excel™ was the actual spreadsheet package used for the main exercises, and Word™ was the word processing package used by students to keep a log of their own progress. HyperCourseware's applications launcher allowed these diverse applications to be effortlessly integrated into a coherent courseware package. From the students' point of view, within this courseware there are examples where launching another application is intended to be very visible e.g., using the actual spreadsheet, and examples where it is irrelevant to the student that another application has been launched e.g., using a MediaTracks movie is just the authors way of implementing a presentation activity. Many similar examples exist within SCALE's courseware e.g., a HyperCourseware template launches MacroMind Director™ to implement colour animations within some courseware on chromatography.
In terms of development hours, interactivity can be sometimes very cheap and sometimes very expensive. At the least expensive, and very cost effective, end of the spectrum there are examples like the Food Hygiene course. (see Figure 2.)
The simulations are used to allow students to explore the performance of small Ethernet and Token ring networks, based on the workings of accurate but simplified models. As well as providing a graphical representation of the working of the networks, which closely resemble diagrams and animations shown elsewhere in the course, the simulations also provide information on the efficiency and speed of the networks. Students can see the effect on the network of changing various parameters and they are encouraged to do this within several assignments and exercises provided within the course. Several preset simulations are provided to show the speed/efficiency of the networks under various message loads and conditions. Students can look at the network operation as a whole or from the point of view of any of the individual stations. In step with the 'animated' view a text box gives a running commentary on what is happening. Users can run the simulation continuously or step through one event at a time.
The student is given statistical information on the speed of the network measured in Mbits per second. This can be for each message received as well as averages for each station and for the network as a whole. The graphs of this information can be printed as required. The users can change the number and time of the messages that each station sends, as well as changing various parameters of the different objects e.g., length of cable between stations. After re-setting, the simulation can be re-run and the performances compared.
Figure 3. is a screen dump from a four station ethernet network simulation. It shows the station after only 109.699 microseconds of simulation time. Station 3 has just started broadcasting a message which is propagating along the cable. Only one other message has been sent and received. Figure 4. shows the same simulation situation shown from the point of view of station 3.
4.1. Implementing the network simulations
The requirements for the simulations were sufficiently elaborate to require the development of a general purpose event driven simulations toolkit first before going on to develop the actual network simulations. The simulation model is made up of individual simulation objects which can be added and linked easily by the authors. The 'views' of this model (i.e., what a user sees) are separate from the model so that many different views are possible e.g., the full and zoomed in views of the ethernet network. This approach was adopted to give the authors maximum flexibility in the creation of the simulations with the minimum of programming. The objects themselves can be extended and refined easily; the ethernet objects are actually refinements of more general network and simulation objects. Theoretically any event driven simulation could be built within this framework.
The simulations were written using HyperCard (an object based system). The simulations toolkit was integrated into HyperCard by conventional means i.e., by using Pascal to program external commands and functions which extend HyperTalk. On the lowest performance Macintosh computers (e.g., a Classic) the simulations run quite slowly but they are still fast enough to effectively inform users. HyperCard's powerful graphics and text handling capabilities make it ideal for providing the 'views' that the student sees. It is through these views that the users gain their understanding of the system and its operation. In this context simulations are primarily about understanding rather than mere number crunching.