Driving a car doesn't always sound like fun. Being bad is no longer cool. Saturday mornings are for sleeping. You're taller than the slide at the McDonald's playland. Your parents' jokes are now funny.
Naps are good.
Hitting girls is no longer considered flirting. You know that those machines in gas station bathrooms don't dispense balloons. Playboy's Playmate of the Month is younger than you. You actually buy scarves, gloves, and sunscreen. You leave concerts and ball games early to beat the crowd.