Teacher

One day in class the teacher walked to the black board and noticed someone had written the word “penis” in tiny letters. She turned to the class, scanned the boys and girls, looking for the guilty face. Finding none that looked guilty, she quickly erased it and began her class.
The next day she entered the classroom and noticed, in larger letters this time, the word “penis” on the blackboard. Again, she looked around the classroom in vain for the culprit, but found none. And so, the teacher quickly erased it again and proceeded with the day’s lesson.
Every morning, for about a week, she found the same word written on the blackboard, each day, written larger than the previous day.
Finally, one day, she walked into the classroom expecting to be greeted by the same word on the board. Instead, she found scrawled in its place:
“The more you rub it, the bigger it gets.🤣🤣