As others have said, this is really an interesting and eye-opening thread.
I agree with sewwhat85's post #31. I recognized myself in some of the complaints (color me embarrassed!) but hopefully not too bad. And I too promise "I will be a better student."
Also, onebyone's comment (post #33) is great. I think the idea of a Do's and Don'ts handout is a viable one and to also go over it at the beginning of class.
I have been in classes where people, even though it was requested that cell phones be turned off, still felt that their conversations were of vital importance not only to them but to everyone in the class. Thankfully the teachers handled this problem in both classes by politely asking the people to take their conversation outside the classroom.
I have taken several classes also where either fabric was to be brought and traded with others so we could get more different colors/tones. There is usually at least one person who has brought really cheap fabric and has tried to trade it for better quality fabric. One lady, even though it was not a "trade around" class, still tried to do it. The lady next to me told her politely that she needed all the fabric in her quilt to be of the same quality so that when she washed it there would not be a problem. She didn't say anything about the quality of the lady's fabric versus her own. I thought this was a very diplomatic way of addressing the issue.