In precalculus the other day, I was demonstrating with my body (ooh, tactile learning) how angles can be coterminal. I propped out one arm to signify my original angle, and then did a windmill type motion with my other arm to signify going around 2*pi times to end up at the same place. I was exuberant in my delivery and went around a couple of times.
A few kids in the front rows started giggling. "Can you do that again?". Giggle, giggle. I realized they were staring at my arms ... specifically at my "tricep" region that didn't stop moving when my arm did.
Hmph. I fake grimaced them and asked if they were laughing at my fat, and warned that they'd be there some day. Little pipsqueaks.