. By Chung Chieh (e-mail), Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada N2L3G1

4. The Dialogue and Confidence Building Questions

The name Computer Assisted Chemistry Tutorial (CACT) implies the original intention of learning by working. After having studied a chemical theory or concept, the student apply it to solve problems. By then, students have acquired some skills, not just memorized some statements. The CACT is based on this pedagogical practice, and self testing is an important part. This part was called the Dialogue in the DOS CACT, because students engaged in conversations with computers. Since the interactivity between computers and users over the Internet requires more time to implement, questions in the Dialogue become Confidence Building Questions in the Internet CACT.

4.1 The Dialogue

In the early DOS CACT, the self testing was done in the form of a Dialogue between a student and a computer. A Dialogue consisted of a series of questions, and the computer gave the user one at a time. Since programming a computer to process students' input is a difficult task, we used questions that require short answers. A complicated task is broken down to many questions, and students were asked to provide key answers in steps.

For each question, answer-response pairs were prepared. The computer gave a corresponding response to the student's answer. The responses pointed out some common mistakes used in deriving these answers. A mark was given to indicate the quality of the answers, but it was not recorded.

A student could answer a question as many times as he or she wanted. The purpose of the Dialogue is to build students confidence and to acquire skills by solving problems. Setting up answer-response pairs in the Dialogue was a very demanding task.

Some concepts or theories can be taught by asking a series of related questions. Some modules were made up this way.

We can also give a number of problems fo a subject, each requires a different application of the same concept or theory.

In the early 1990s, students came to the computer room for the CACT. Watching them working on the problems was a rewarding experience, and students also directly interacted with me. After the network has expanded to campus wide with many computer rooms, and especially after having converted to the Internet CACT, I miss the opportunity for direct human interactions.

Over the years, some students have use CACT extensively, and a few have even point out the errors and made suggestions to improve CACT. Jason Ekert a former student in the course, proof read the files after he completed these courses. Of course, I appreciate having the feedback very much, and some of them realize it.

4.2 Confidence Building Questions

Questions in the Dialogue of the DOS version of CACT have become Confidence Building Questions of the Internet CACT site. Common browsers do not provide interactive responses to corresponding answers in the form of Dialogue. Java applet or other programs have to be implemented. We have not had the time to develop a Dialogue approach to the Internet version of CACT yet.

In the current version, we put all the questions together, and provide hints, suggestions or considerations as well as hidden answers. Over the past two years, we have tried various techniques in the Confidence Building Questions. On some pages, we specify the skills students acquired in solving these problems.

Rather than learning the chemistry directly from the computer screen, Many students print the web pages in the Internet CACT for their study.

Having the appropriate number of quality questions in a subject is important. We are constantly improving the Confidence Building Questions of the Internet CACT. Time and effort are required to read the pages and make changes. Thus, building a web site is a real labour of love.