As multimedia makes concepts easier to understand, retention and application do not automatically follow as they did when students wrestled with opaque words and text. A self-study aid, MoBy, has been developed, as a companion to multimedia presentations, to help students retain and apply the knowledge gained in these lectures. MoBy uses a classical approach supplemented with hypertext, graphics, sound, and animations and it is available over the World Wide Web here. Problems have included cross-platform support and student over-reliance on MoBy alone. Nevertheless, MoBy has been highly successful, as judged by several hundred written student evaluations, and instructor perception.
The course is BCM410A, "Molecular & Cell Biology". It is a required first year course for medical students, taken by about 100 students each Fall. There are no teaching assistants. The course comprises a lecture every weekday for 9 weeks-45 lectures. Most of the lectures are given by the two co-instructors of record, Michael J. Holland and Harry R. Matthews. Matthews' material, on Protein Structure and Function in the Human Body, is presented with extensive use of multimedia, exploiting the power of graphics to illustrate the abstract concepts involved. The MoBy Study Aid covers this part of the course.
The students are all highly intelligent and motivated. However, their backgrounds are enormously diverse; some are straight from a B.S. in Biochemistry or even a higher degree; others have no Biochemistry background; and many have been out of School for at least several years. Students' computer skills vary from none to those of a professional software engineer.
Student performance is evaluated by two multiple-choice examinations, a mid-term and a final. The quality of the course and the performance of each instructor are evaluated by written, anonymous, student evaluations and by peer evaluation. Student evaluations are both quantitative and qualitative and are available for 4 years of deployment of MoBy. Student response in each year was over 90%.
The questions asked in 1995 are as given in Appendix 1. The details of the questions change slightly from year to year but the questionnaire has not changed significantly in the last five years.
ToolBook provides excellent handling of hypertext, which is the basis of the application. About 420 multiple-choice test questions form the core of the study aid. Most of these questions are of the "choose the best answer out of five choices" variety. For these questions, every answer choice has a page of explanation giving detailed information, test-taking tips and whether the answer is right or wrong. These answer pages often include graphics. Probably the most useful feature is the glossary, which contains over 800 pages of detailed information, illustrated by graphics and some animations. Each glossary entry has one or more words that lead to it and every time one of these words appears in the complete application, whether questions or answers or glossary pages themselves, there is a hyperlink to the glossary page. A question page will typically have 12 to 15 hypertext links per question and the same density is maintained throughout the study aid. Since there are over 3000 pages, this makes over 40,000 hypertext links, probably well over 40,000 because the answer and glossary pages are often contain much more text than the questions. Thus dense network of links allows a student to "drill down" to a level that is accessible and then move up to the level needed to answer the questions. Intelligent navigation "buttons" keep the student from getting 'lost".
The questions can be accessed by subject or at random. The glossary can be accessed directly from an alphabetical index. Since MoBy is designed as a study aid, it includes no form of assessment or tracking of a student's progress. Such facilities can be easily added in ToolBook but it was felt that they might inhibit the students from using the aid freely. I wanted them to explore the glossary, find the animations and generally get immersed in following their interests, without worrying that someone might be metaphorically looking over their shoulder.
The 23 lectures are given as PowerPoint presentations using a video projector linked directly to the computer so that the animation features of PowerPoint can be used. The PowerPoint presentations are available to the students in the student laboratories and on the World Wide Web. Partial Macintosh support is available for these presentations. Printouts of the "slides" are not provided due to the cost of color printing and the lack of animation on paper. Nevertheless, students do print out the slides and the instructor has a neutral attitude to that practice.
Students communicate with the instructor through email and the instructor replies individually or, through a mailing list, to the whole class. Email is read and responded to every weekday morning. No attempt has been made to develop email discussion groups or newsgroups or chat sessions.
In addition, there are traditional office hours daily and an informal review session weekly. There is an extensive printed syllabus, sold through the bookstore and also available on the WWW.
Student learning can be classified into several stages. For this discussion, I will use a highly simplified classification into three stages, namely comprehension, retention and application. For the first stage, the student needs to understand the material. This is usually achieved through the lecture format, although it may also be achieved through individual study of textbooks or other materials. In many subjects, including the natural sciences, the use of graphical illustrations is very important in helping the student understand the descriptions and concepts which are sometimes abstract and counter-intuitive. In the lecture, graphics may be presented as drawings on a black- or white- board, as transparencies on an overhead projector, as projected slides, as video on a television screen or as computer images through a video projector. The black/white board has the advantage of showing each graphic in steps as it is built up. This can be mimicked with the computer by using animated slides in which components are added one by one. The computer can also play animations, providing an extra dimension to the graphic. Careful use of graphics can make it much easier for students to understand the material and they may be misled into underestimating its complexity, since they haven't had to struggle to comprehend it. This may lead to difficulty in reproducing the material, i.e. explaining it to others, and to difficulties in using the material. Thus, it is imperative that the addition of sophisticated and successful graphics to a lecture class be accompanied by material that helps students retain and use the material presented, to complement the easier comprehension.
The MoBy study aid uses the classical approach to the retention and application issues, namely asking questions. The questions that form the core of the study aid are those that have been previously used in internal examinations, which provides a powerful incentive to students to use MoBy. No other incentive is provided nor, apparently, needed as MoBy is widely used. The critical component of MoBy is the extensive glossary and the explanations of wrong as well as right answers, often in considerable detail. Thus, MoBy is truly a learning aid rather than a testing tool. Nevertheless, students need to be careful to understand that MoBy is a secondary learning tool to be used after the material has been covered and understood, at least at a superficial level. MoBy will help deepen the understanding and, by engaging the student with the material, help with retention and application.
Apart from the general question of reinforcing the lecture, MoBy helps to address the problem of varying student backgrounds, since the glossary allows students to go back as far as necessary to understand each problem.
Student appreciation was measured with a questionnaire that included standard questions about the course as well as specific questions about the MoBy study aid. The questionnaire used in Fall 1995 is provided in Appendix 1. The scale is 1 poor, 2 fair, 3 good, 4 very good, 5 excellent. Figure 1 shows how MoBy fared in the five years, 1991 to 1995.
Figure 1. Student evaluation of MoBy, 1991-95.
The students rated MoBy very good, with somewhat higher scores in 1992 and 1994. The reasons for the fluctuations are not known but there are some factors to consider. The first year, 1991, was very experimental. 1993 was an unusual year because of the presence of a significant group of students who did badly on the examinations. The drop in 1995 compared with 1994 was, at first, surprising but informal interviews with students suggested the reason may be that feedback from the 1994 class about the value of MoBy led the 1995 class to place too much reliance on MoBy and used it inappropriately to replace the normal lectures and associated studying. Since MoBy was not designed as a primary study aid, it failed to meet their expectations. Other problems are that MoBy only covers the material in 23 of the 45 lectures in the course and that there is no Macintosh version. In spite of these factors, MoBy still garnered a very good rating.
It is interesting to compare MoBy's rating with that for other components of the course and this is summarized in Figure 2.
Figure 2. Student evaluations of various components of the course.
Figure 2 shows that MoBy ranked as one of the most valuable parts of the course, much higher than the textbook assignments and the coop notes and comparable with the lectures. The syllabus was the most consistently valuable item. In some years, 1992 and 1994, MoBy was at the top of the list but over the other years there was significant variation in the score given to MoBy. The decline in textbook use is in line with trends elsewhere.
MoBy is greatly appreciated by students, especially those who can take the application home and work with it there. The instructor's perception is that it helps students greatly with retention and application but doesn't replace primary learning from the lectures and syllabus. Students regard MoBy as much more valuable than assigned readings in textbooks.
The format works well and requires very little computer expertise. The program, ToolBook, is very appropriate for this type of application because of its strong support for hypertext. Nevertheless, it was necessary to write some utilities to automate some of the authoring processes. ToolBook suffers greatly from lack of Macintosh support. This may be alleviated by the forthcoming Internet-friendly version. Most of the work in developing MoBy was in writing the questions, answers and glossary.
In informal conversations, and in their written comments, many students are extremely enthusiastic about MoBy as a study aid. It seems likely that this kind of approach would be of quite general application, especially in courses that use multiple choice questions in their examinations.
The version of MoBy that was used last Fall can be downloaded from here and run on a computer using the Microsoft Windows operating system.
Harry R. Matthews,
University of California at Davis
Davis, CA 95616