In lesson 7, you introduce commenting (very important) as well the concepts of preconditions and post-conditions. Last year, I was pretty strict about requiring pre- and post-conditions be given for every function. This led to much frustration among some of the students as they had a real hard time with these concepts. It hung some of them up more than I think was worthwhile this early in the game.
This year, I am thinking of requiring a comment describing each function, but not requiring pre and post-conditions.
I am interested in hearing what others are doing and how it is working.