Those nine words just cost you your life. Oh, and if you happen to be involved in the duck duck goose game, don't continue to play when the teacher comes back. That goose will most likely suddenly be very involved in a copy of Moby Dick . Another wonderful adventure is the bathroom. Of course, the rules to the bathroom are very different depending on your gender.
All guys know the rules of the urinals.
Also, don't urinate in pairs. When men see men standing and peeing next to each other they assume that they are lovers. It's a guy thing. Now, women are very different in the school bathroom. This is your best bet, but if you do go in there during another time, be sure to follow the rules.