In terms of advantages, computer based course materials have in many respects a brighter plumage than the dull colours of the 'chalk and talk' method, yet evolution has favoured the latter.
This success is probably due to cost effectiveness and flexibility, and it is no coincidence that these are attributes of evolutionary winners in the natural environment.
Perhaps in order for CAL to become as widely adopted as 'chalk and talk' teaching, it will be necessary for it to take a trick from nature's book and copy some of the features of its competitor whilst retaining its inherent strengths.
Over the past couple of years I have developed a method which I call 'Live Authoring'. This method enables rapid, low cost preparation of course materials and will be described in detail in the remainder of this article.
At this stage I would like to point out that I am a Physicist, with no knowledge of Economics, but with extensive experience of Live Authoring in the fields of Mathematics and Physics. The writing of this article was encouraged by Economics colleagues who saw potential applications in Economics, a subject which traditionally relies quite heavily on the 'chalk and talk' method of teaching.
The Live Authoring method centres on the simultaneous recording of the lecturer's hand-written notes and voice as a lecture or tutorial is given. The recorded voice can then be played back and the hand-written notes reconstructed in real time to give the impression of the original tutorial.
In this way Live Authoring permits course materials to be developed concurrent with the delivery of a normal lecture or tutorial, minimising development time.
On the other hand, it is of course possible for the recording to be carried out off-line and away from the teaching environment if one so wishes.
All that is required to implement the Live Authoring method is a standard Pentium multimedia computer, a graphics tablet and pen, and suitable software. It is even possible to put together a system which will fit in a briefcase using a portable computer, tie microphone and a small graphics tablet. In terms of training, relatively little is required to enable the lecturer to use the method: the knack of writing on the tablet is easily acquired after a few minutes of practice.
Once the material has been recorded, it is then possible to edit the hand-written and audio elements and to add additional media if required, although I would caution from experience that the benefits of low development time and cost are somewhat compromi sed if one gets involved in too much editing.
If mistakes are made during an explanation, the lecturer would normally correct them at the time of recording, making the task of editing simply a matter of lifting out the correctly explained section from the presentation.
In addition to the creation of course materials from scratch, it is also possible, copyright permitting, for the lecturer to take existing images, videos and presentations and to annotate these, furthering the use of existing resources.
Once prepared, Live Authored course material can be delivered in a number of different ways such as on CD-ROM or over the Internet. The Internet makes it possible for material to be allocated automatically to web sites as it is recorded so that students c an access it immediately.
Figure 1 represents a snapshot of actual Live Authored content taken from a colleague's classroom lecture on profit maximization. Careful readers will note that it contains some sloppy notation -- inconsistent symbols for derivatives, etc. -- typical of t he mistakes that one may make in the heat of a classroom presentation. One of the attractions of Live Authoring is the accurate record it can keep of extemporaneous presentations during a lecture. Reviewing these after class, instructors can catch slips l ike those in Figure 1 and make corrections in the next class meeting the pretext for reviewing important materials.
Every lecturer can remember times when explanations have gelled and the audience has come away with a clear understanding. Equally, every lecturer is probably also aware of the repetition inherent in delivering a course term after term and the need to mai ntain a consistently high standard of explanation.
If a lecturer were to employ the Live Authoring method on a regular basis, there would be an automatic build up of explanations from which could be selected the very best. This idea could be extended to draw upon the work of other lecturers thus forming a pool of 'super' explanations and worked examples. The lecturer's time could then be spent helping individuals and improving explanations rather than repeating material time and again.
The preliminary results of an informal evaluation of the results obtained by students using Live Authored content in Maths and Physics suggests that performance as measured by student grades at the end of a teaching module equals that of a live classroom teaching approach.
Also of interest were the subjective opinions of the students, in particular the weaker ones, who said they were much more inclined to go over an explanation they did not understand again, whilst sat at the computer, than they would in classroom environme nt. This is probably due to the lack of peer pressure when sitting at the computer and in my opinion a significant benefit of Live Authored content.
Finally, coming back to the essential idea that CAL creation needs to be as spontaneous as 'chalk and talk', all future developments of Live Authoring will revolve around the need to make the technology as transparent as possible, leaving the lecturer fre e to focus on the art of high quality explanation.
In the mean time, should any queries arise with regard to the setting up of Live Authoring projects, I can be contacted at the following email address: