One I haven't seen here yet:
The teacher had set the topic for show and tell as things that had changed a persons life
It came to little Jhonny's turn, and the teacher cringed as she invited him up to the front of the class.
He walked up to the chalkboard and drew a period.
The teacher asked how a period could change a persons life.
"Well", he said, "At breakfast this morning when my sister said she had missed her period, my mother fainted, my father cursed her for a whore, and the neighbor boy commited suicide."
or something similar, can't remember it correctly. Got the punchline correct, I htink.
