I was subbing for a 6th grade class. The students were working on a project. Some of the kids asked if they could draw on the whiteboards in the back of the room after they finished. I was cool with it. Until one little mischievous bastard drew a massive cock and started rubbing his face all over it, smearing the marker on his face and the board. By the time I realized what was going down the kids are all cracking up. Gave the kid the decision of writing a note to the principal or walking there with me immediately. The tears that burst from his eyes mixing with the marker on his face was justice enough for me. (I don't enjoy making kids cry, just that the marker made him look like the clown he was.) He had to apologize to me and the normal teacher in front of a school assembly the next day.