For those who've never encountered stretch marks before: [link]
Yeah. After telling us about all those nasty STDs, it would'v been nice to know that the big red streaks that suddenly showed up on my hips weren't gonna kill me.
By the way, this isn't the place to discuss to what degree you agree or disagree with the idea of sex education in schools (notice how I called it "health class?") There are plenty of online forums for that.