I've told some of my friends about this convo I had with one of my male gym teachers,and they all thought it was creepy, and sounded perverted in a way. It was just a short convo, really. Ok, so this is how it went:

Teacher: Thank you for smiling today

Me: I'm not smiling

Teacher: You will be

Does it really sound creepy? What do you think?

...and because I couldn't keep a straight face, I laughed/smile and he said "there you go" :P