When each one of my children began dating, I had some really good talks with them about respecting their own body and the body of the one they were dating. I said things like, "Don't spend a lot of time necking." "Respect her enough not to touch her where a two-piece bathing suit would be on her body." "If its good it can wait."
As parents we have to be very sensitive to our own children. We are the only ones who have been with them since birth and we are the only ones who should teach them such a subject. We can't expect a school system or a website to do our job for us.
Thank you for raising great kids!
You can expect the school system to do everything they can to undermine your values. If you have kids in government schools, and you love them, then get them out of there.