Not a music teaching experience, but hilarious all the same... (warning: maybe this post should have a 12A rating!)
I'm 19, working in a secondary school with a science teacher. We've just finished a lesson on human reproduction with the top set Y8 class. At the end one particular student, not the best behaved and rather cheeky, but bright like all the others in the class, hangs around and catches me at the end.
"Miss, y'know when you have an erection?"
I honestly can't remember the expression on my face, but I vaguely recall I nodded while looking as serious as I could manage.
"Yes?"
"Well, where does the bone go?"
At this point, I wondered if he was trying to wind me up / embaress me. But he seemed quite serious, and was, after all, only 12. So I bit my lip and did my hardest to explain the fundamentals of a certain male organ, concluding with:
"So, it gets firm when blood is pumped in, a bit like when you blow air into a balloon at it gets bigger and firmer."
(At this point, I realised to my mortification, I had also been subconciously demonstrating this expansion with my hands.)
The 12 YO pupil gave me a horrified look.
"What, y'mean... it can't explode like a balloon can it?!!"
Still struggling to keep a straight face, I assured him this couldn't happen, at which point the situation apparently got too much for him and he ran out of the classroom... allowing me to collapse in hysterical laughter.
I still don't know if he was having me on or not, but I hope I didn't scar him too much!