College Teaching

I am going through the process of my second year review at work. Student evaluations of my teaching are on my mind - a little too much! This has made me remember some of my favorite college teachers and classes. What do you remember liking most (or least) about your college professors? What things did they do to make you think they were awesome and enthusiastic? What were the characteristics of the courses you thought were challenging?

And, yes, if you are wondering, you will be tested on this! ; )