1. "The professor in the course you teach went over a topic in class and made a serious mistake. Although the mistake was pointed out in class, the resulting explanation was rather unclear, so much so that the students are in complete confusion regarding that material, which forms the basis of the lab your students are about to perform. Your job is to clarify the error and make sure the students have a sufficient working knowledge of the underlying concepts to do the lab and hopefully to understand it as well."

2. "You have returned the first problem set and it is clear that there are some elementary requisites that a significant number of students do not understand. For example in a calculus or physics course there may be a misunderstanding of the meaning of (and the calculation of) partial derivatives. Present your approach for identifying the misunderstanding, and for clarifying it for the students. Be interactive and ask questions since this is an idea they should already understand but apparently do not."

3. "The Professor made a reference in class to a subject related to the one you are teaching. He did not explain the reference and some students really didn't understand it. You need to explain the related area. For example, if you are teaching an introductory CS course, perhaps the instructor referred to a compiler."

4. "The professor in the course you teach went over a problem in class and made a serious mistake. Although the mistake was pointed out in class, the resulting explanation was rather unclear, so much so that the students are in complete confusion regarding that material. Your job is to clarify the error and make sure the students understand the underlying concepts."

5. "It is early in the semester and you are trying to help the students develop some intuition about how to approach the problems in the course. Present your approach to solving problems in the field at the level of your students' understanding."