Years ago, I was teaching a scrapbook class for a gal who had just signed as a consultant. She had her mom, sisters and some friends there, along with an assortment of young kids. I wasn't too thrilled about the kids, but was hoping they would stay in the other room so we could concentrate.
One of the kids was her nephew (about 8 or so), whose mom was at the class. This kid was determined to cause trouble, racing around, throwing things, yelling, and generally wreaking havoc. I continued to try to teach the class amid yells from his mother and others at him to "stop that", "calm down", etc. I tried to keep everyone on track. Finally the kids all ran upstairs, and I thought, "Good, maybe they'll stay up there and we can have a peaceful class for a while."
After a few minutes, the nephew comes bounding back down the stairs with the other kids, YELLING at the top of his lungs, "MOM!! MOM!! Look what I found!! Under the bed! What is this thing??"
It was a... ummmm... "personal stimulation device"! I think I gave up at that point...