One day the teacher walked up to the blackboard and she noticed someone had written the word 'penis' in tiny small letters. She turned around, scanned the class looking for a guilty face. Finding none, she quickly erased it, and began her class.
The next day she walked into the room and again saw, in larger letters, the word 'penis' on the blackboard. Again, she looked around in vain for the culprit, but found none, so she erased the board and proceeded with the day's lesson.
Every morning, for about a week, as arrived at class she found the same word written on the board, only each day's word was larger than the previous day's word.
Finally, one morning she walked in, expecting to be greeted by the same word on the board, but instead, found: 'The more you rub it, the bigger it gets!'
The teacher says, "Okay, class, we're going to play a game today. I want everyone to give me a sentence with the word 'perhaps' in it."
Claude says, "Perhaps if we are good, the teacher won't give us any homework." The teacher says, "Very good, Claude."
Mary says, "The sky is very dark... perhaps it's going to rain." The teacher says, "Very good, Mary."
She calls on Little Johnny in the back. "John?"
Little Johnny says, "Yesterday, when I got home from school, my sister and her music teacher both had their pants down to their ankles. Perhaps they were gonna shit on the piano."