There's not an age too early. Children are aware of sexual differences and are full of questions.

I was 7 when sex education began at my school. It was only one lesson but gave me an idea of procreation. The next lesson wasn't until I was 12 which was in far more detail. But by that time I was very aware of sex in general. Children should be educated often so that they are more aware of their own bodies.

10? I knew about those things when I was five, and my mom bought me a book. It was fun sitting through my teacher awkwardly reading through a script, and the other students fearing for their life. The vice principal even had to teach the boys! As well as one of the third grade teachers because there weren't enough male teachers. The boys all finished early and got extra recess ???? That made me mad. Ideally sex Ed should start as soon as a child can understand your words.

I think parents shoudl be willing to answer all questions about this no matter what the age of the child. In countries where this is doen there are much lower teem pregnancies and much lower STD rates.

Unfortunately, many parents (at least in the U.S.) wont' ever talk to their kids because they either dont' know the answers themselves, or they are uncomfortable talking bout sex in general.

I believe the sooner the better is best around 6 or so. I met a boy this past summer who at age 4 was carrying on discussions with adults in a mature fashion comprehending most if not all that was discussed. I think a curriculum should be developed that recognizes their youth but also recognizes their ability to comprehend things we don't realize they do.

If they ask the question, they should get the correct answer. Parents should be in charge of this, and shouldn't be afraid to teach their kids that sex and procreation are part of life. They shouldn't shy away from it and they shouldn't fear having their children know about it. There would probably be a lot fewer assaults of the sexual nature if they were educated properly.

Since teens will "educate" themselves on the internet with unrealistic porn and imagine that that is what sex should be like, inaccurate expectations and misogynous patterns will be generated whether we like it or not (not that all porn is misogynous, but so much is). Therefore, it's important that sex education in junior high (and maybe earlier) get out in front of the issue of depictions of female sexuality with more accurate information - but in a sex positive way. Also, more discussion of homosexuality, asexuality, and transgender issues is necessary. The purely "plumbing and prevention" approach to sex ed is outdated. Here are a couple relevant articles: [telegraph.co.uk]
[time.com]
[plannedparenthood.org]

I would take it a step further: Having good sex. Flirting (I need all the helps), foreplay, what holes, when and where. Things like climax times would have been useful: It takes some people 5 minutes to O and others 40 and some can't even.