A father and his son go into the grocery store, when they happen upon the condom isle.
The son asks his father why there are so many different boxes of condoms.
The father replies: "Well, you see the 3 pack? That's for when you're in high school. You have 2 for Friday night and 1 for Saturday night."
The son then asks his father, "Well, what's the 6 pack for?"
The father replies: "That's for when you're in college, son. You have 2 for Friday night, 2 for Saturday night, and 2 for Sunday morning."
The son then asks his father, "What's the 12 pack for?"
The father replies: "Well, that's for when you're married. You have one for January, one for February, one for March….."