Forget it, they should learn when their right time comes! Nobody needs to be schooled about it, it’s innate. The basics are learned at biology classes and that’s more than enough till the right time. Don’t encourage waywardness. Teach youngsters around you to focus and carve a niche for themselves is various good endeavors of life. Sex is self taught besides you are two in the act , if one doesn’t know the other will help out and scores are only measured by pregnancy! And that’s most passed subjects by the educated and uneducated! Just the basics for self awareness and defense which is taught in homes schools and churches .