how/when did you learn about sex?

some time in the middle of first grade a new girl came to our school, and few days later she brought me and a few other kids up to speed. as i listened i realized it's some kind of a big deal, and couldn't wait for the first chance to break the news to my two best buddies, a boy and a girl. i met them during recess, and the conversation started like this:

me: have you heard about fucking?

she: no, what's that?

me (genuinely sad): oh, it's too bad that you're a girl. you won't get to fuck, you'll get fucked.