Self control has only existed since 1504?
I don't know how old you are or what you've been exposed to, but teens have sex. They do it in other cultures, and they've been doing it for a long time. Pretending something doesn't happen will result in teen pregnancy, disease, and other fun things like that. Accepting its existence and then educating teens about its risks is important. It's also important to help teens cope with puberty.
As far as the issue of teaching about homosexuality: Though it may conflict with your morals or beliefs, for whatever reason, the truth is that some teens are gay. If they aren't aware of that possibility, or aren't reassured that there's some sort of acceptance for that, they might become confused or depressed. Once again, puberty can be a maelstrom of conflicting and confounding emotions.
You seem to want to impose an idealistic sort of innocence upon pre-teens and teens. Besides, forcing your morals upon an entire nation would be tantamount to fascism, no?
What confuses me about American culture is the regard for sex as this great evil. It's an interesting twist on Judeochristian mores. If you want to address problems with kids, perhaps the rampantly violent media culture would be a good place to start.
This idea of completely stopping premarital sex would seem completely reactionary in nature, except for the fact that there is no point to revert to when premarital sex did not occur. Even during the Victorian era, which attempted to appear prudish, had pre-marital sex, as well as teenaged prostitutes who slept with older men. The Puritan idea of courting was not just a date. Going back to my comment about homosexuality, Greek culture accepted sex between men and boys. There are countless historical examples. Essentially, the point I'm trying to make is that some of these impulses are part of humanity, not just a societal "evil" which must be eliminated.
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