I remember knowing some girls who were the exact same way, frankly. One family of three sisters all had at least one kid by age 15, and they were all damn proud of it, too. There's more, but you do not want to know. Early 80s. And those were just the most extreme ones. Yeah, the horny teen movies of the late 70s and 80s exist for a reason.

The problem is the misuse of the word "child" to include the pubescent, because people confuse biology with legal stuff. And there seems to be great reluctance to teach simple self-control, it's like balance between "anything goes" and "abstinence" is an alien thought to most humans. That being said, my own sex ed experience was this: it was grade 8, co-ed, and purely matter-of-factual, and focused a lot on syphilis (AIDS wasn't a thing quite yet.)