But, quite simply, they don't always. My parents never bothered to tell me about any of those things. Sometimes parents can't be bothered, sometimes they're too busy and for some there may be religious reasons (such as being Roman Catholic and discussing the idea of contraception) that they don't tell kids certain things. A curiculum would make sure that every child has the same chance at learning what the government sees as vital for their safety and development. Children go to school not only for academic reasons, they go there to learn. School has never been all about careers. Most parents don't teach their children how to protect themselves. If they care or have money, they may send them to martial arts lessons, but usually it's a matter of 'don't go in dangerous places'. I think breakfalls are something quite vital for children to learn as people fall and get injured all the time. At my jiujitsu club there's a story about one of the sensei who fell from the roof of his house and instinctively did a breakfall technique, which probably saved his life (well, he wasn't exactly in one piece but he did set the record for the highest breakfall height at our club!). I think it's just as important as learning about contraception, and more important than some of the 'lesser' subjects.