A man walks into a drugstore with his 8-year-old son.
They happen to walk by the condom display, and the boy asks, "What are these, Dad?"
"Those are called condoms, son. Men use them to have safe intercourse." the man replies matter-of-factly.
"Oh I see," replies the boy, pensively. "I've heard of that in health class at school."
He picks up a packet of three condoms and asks: "Why are there three in this package, Dad?"
"Those are for high-school boys. One for Friday, one for Saturday and one for Sunday," the man replies.
"Cool!" says the boy. He notices a six-pack and asks: "So who are these for, Dad?"
"Those are for college men," the dad answers. "Two for Friday, two for Saturday and two for Sunday."
"Wow!" exclaimed the boy. "Then who uses THESE?" he asks as he picks up a 12-pack.
"Those are for married men. One for January, one for February, one for March..."