Experts Teaching Novices

As part of the research I'm doing for my Ph.D. dissertation, I'm reading some research on training methods intended to bring about long-term retention of skills and transfer of those skills into new contexts. It turns out that some of the training techniques that give you high marks during the training will cause you to forget your training more quickly later. The converse is also true: When techniques that have been shown to improve long-term retention are used during training, the trainees actually perform more poorly while the training is taking place. The research also shows that intensive programs are much more likely to lead to loss of skill than programs that spread the same training over a longer period of time (but you knew that, didn't you?).

There were some other interesting findings, but one of the things that struck me was the section on expert modeling of a skill. The idea is that the expert shows the novice how to perform the task (be it repairing a computer or finding the roots of an equation), and the novice is supposed to learn from this demonstration. The problem is that almost by definition, most experts have internalized the task to the point that they aren't consciously aware of all of their thought processes while they are performing it. As such, they can't convey all the procedures needed to do the task to the novice. This is the root of the observation that many college instructors are very good at what they do, but they can't teach it worth a darn.

Teaching is an art, quite apart from knowledge of the content area. In order to teach, you have to not only understand your own thought processes, you have to create a mental model of your own thought that can be transferred to the student. You also have to keep a model of your estimation of the student's understanding in your head as well. Finally, you have to come up with an efficient way of modifying (or helping the student to modify) the student's mental model until it matches your own. No easy task! I'm amazed they let college professors even try it without explicit training in education...