A fourteen year old child, or young adult, in my opinion, should know everything there is to know about sex. I think that because their bodies are already starting to change, they will need to know what is happening to them in order to figure out why they feel how they do. If somebody would have told me what was going on the first time I had an erection, maybe I wouldn't have been convinced that my body was about to explode. A fourteen year old person is old enough to comprehend what sex is about, or at least the mechanics of it. I know that it takes a person much older to understand the emotional consequences of sex, but regarding the mechanical actions of sex, a fourteen yr. Old brain will handle it just fine. .
What an 18 yr. old should know about sex.
I think, after much consideration, that an 18 year old person's sexual awareness has a potential variance genderwise. I think that males are much more aware of their penises and what they have the potential to do, as masturbation is seemingly more common and frequent among males. However, I also think that women whose bodies are developing also need to know as much or possibly more than males as the ramifications of sexual activity can be much more detrimental and, obviously, long term. Essentially, I believe that any person who has reached the age of 18 needs to know what they should and shouldn't be doing. I believe that this is absolutely necessary. So, if asked what they should know, I would respond that they need to know everything: the good, the bad, and where their views on all of it stand.