Oddly enough since I came from a fairly populated area, I only had one student teacher my entire school career as a student- Peter Hall.
Mr. Hall took over my junior year high school health class. He wasn't particularly talented and my guess is he did not receive a passing grade for his efforts (as I plodded through my own student teaching I thought about Peter Hall quite a bit). As a class (and I can only speak for my 48 minutes a day with him), we were awful to him. Since we were juniors were both naturally cool (in our minds) and super big pricks (in everyone else's). We smelled blood on this goof and went for the kill daily.
The ultimate low moment started when it was time for the boys and girls to separate. The cooperating teacher (a female) took the girls and we were left with Mr. Hall. His task was to demonstrate how to put on a condom. This kind of shit is awkward enough on it's own, but Mr. Hall producing a banana to serve as his model erection probably didn't help things.
Things went from awkward to pathetically embarrassing real quick. We sat their silently watching poor Peter Hall. He stood at the front of the room fumbling and struggling... to get the rubber out of the package. Ouch.
I gotta tell you... it really killed the mood.....