Two boys visit a nurse to trick her into touching one of the boys' privates. They pretend they've been practising karate and that the one boy has been caught in the balls. The nurse checks his balls and says they should be more careful when kicking. Of course it would be better if the nurse thought a girl had done it, but it's not bad.

http://www.youtube.com/watch?v=TiyBW-gZ9Hk