First, I agree with you that society is over-sexualized. I think there is a lot that, I personally, find inappropriate. That said, there is a LOT that society is closed about. Personally, I had "sex education" in my private, religious school. Basically, it was split up between our freshman health class and sophomore biology class. Truth told, my parents never game me "the talk."
When I was older and doing some work in a public, inner-city high school, I was helping out with a "advanced" English class. In the class, the word "erection" was used in the book, and several girls came up to me to ask what it meant. I thought they were trying to "be funny" as I was new, so I sent them to the teacher. Turns out, they had no idea. These girls LITERALLY had friends their age who had babies. I asked the teacher about their lack of knowledge given their situations and she said that while they are supposed to cover sexuality in middle school, like other subjects the level of education is exceptionally low. According to her, these girls were extremely unlikely to have a proper understanding of sexual matters, despite many of their friends being sexually active (although, according to the teacher, probably not them).
So, IMO, information should be made more available. And, IMO, by high school kids should have basic, factual information freely available. I understand people's concerns that it might be "going to far." IMO, it should be a part of health and biology classes, as it was for me. I know the unit about contraception failure rates made a huge influence on my decisions as a young man.