Ugh...I have such mixed feelings about this.
I'm a kinesthetic (hands-on, learn by doing) learner, so from a purely practical point of view, this would have been my preferred way to learn. (Like JR said, "what better way to learn about how a car works than by going to a mechanic?")
And morally, I don't have any issues with sex before marriage (or love), so that wouldn't have been a problem for me personally, but I know it would be for a lot of people, especially here in the United States. So if such instruction ever WERE made available, I wouldn't think it wise to make it mandatory for families or individuals that had moral/religious issue with it.
I also wouldn't think that such instruction should be geared specifically toward the heterosexual population (as many folks here have already pointed out). I'd lean toward a system that teaches everyone how the male AND female bodies work, regardless of sexual preference.
And yes, as Madeira pointed out, children ARE vulnerable and easy to take advantage of, so I don't think a child should ever be REQUIRED to allow someone to touch them sexually.
Realistically, most adolescents are going to experiment. It would be nice if they at least had ACCESS to sufficient information, education and preparation (from someone who wasn't also in the earlier learning stages) in order to do so safely. So like Elnoa, though I don't think hands-on sexual education should be mandatory or forced, I do think it would be nice if adolescents did have "the freedom to experiment, and seek out a professional if they want."