Effective Technique for Presenting Demonstrations

1.  Show the demonstration arrangement to the class without performing it. Let the class think of what it might do if it were operated.

2. Describe the demo and let the class come up with the various possible results.

3. Take a vote on what they think the outcome of the demo might be.  This is a nice place to use the PRS devices that have become popular as of late.  A cheap alternative is lettered or numbered cards that the students can hold up.

4. Allow let the students to discuss the question among them to see if their individual logic can stand up to the scrutiny of others.

5. Have another vote before you do the demo to see how many of the students were able to change each other’s convictions.

6. Perform the demo so that every individual can see how his or her ideas conform to the actual experimental results.

7. Discuss the experiment further so that each student is forced to confront the errors in his or her physical concepts - and to ultimately adjust their thinking to conform to reality.

It turns out that using this general procedure has several very interesting results.  The students actually seem to learn more physics and it appears to stay with them longer and mean more. They remember the experimental results of the demonstration properly.