I took s Human Sexuality class in college. It was actually pretty informative, learned a lot about cultural mores around the world regarding sex and how attractiveness changes from one culture to another.
And also, smiling is universal. I dunno why that one stuck with me or why I didn't know it before hand, but across the world a smile is always a happy/polite thing.
Also learned that on average British men have one of the largest penises. (Average of 8~10 inches)... We also had guest speakers, one was a gay guy talking about being gay and figuring out he was gay etc, one was a cop talking about weird sex crimes and stuff, and another was a hooker.
Was kind of a fun class.