'SEX education," Bill Cosby once said, "may be a good idea in the schools, but I don't believe the kids should be given homework." His joke worked on two levels.

We parents don't want our children coming back and working through sections of The Joy Of Sex on their top bunks. But, more pertinently, many mothers and fathers would rather not be burdened with the embarrassment of the sex-ed conversation. They would rather not know that, as last week's headlines proclaimed, sex education is not working in Scotland, teenage pregnancy rates are rising, and the burden of teaching the birds and the bees is to be thrust back on them.

According to NHS Greater Glasgow and Clyde, schools have failed to deliver in this field and as a result, teenage pregnancy has escalated. So the board has launched a campaign to encourage parents to talk to their young children from about puberty, relationships and sexual health. Schools have failed to deliver on this issue, they say, and as a result, teenage pregnancies have escalated. "You are the child's first and most important teacher," says their leaflet.

I would go further. I would suggest that what we currently know as "sex education" should be dropped from the school curriculum altogether – not only is it not "working" in terms of preventing pregnancies, but, like most public health messages, from five-a-day to alcohol unit guidelines, it represents a pointless gesture in the face of the major cultural pressures of the day.

If we really want to open up our society to talk about sex, then we need to give the subject back not just to the parents, but to siblings, friends and other amateurs who always were the repositories of knowledge. In the days of the internet search, no teenager needs an expert to teach these secrets.

Indeed very few young people these days can have missed the instructions on how not to make a baby. Just because you know something, however, doesn't mean you are able to act accordingly. As one friend of mine, with teenage children, says: "Many teenagers can't keep track of their mobile phone. How can you expect them to take a contraceptive pill every day?" And, as she adds: "The problem really lies in teenage drinking, and losing control, as much as attitudes towards sex."

That's not to say we don't need to talk about sex – just not "educate" in this way. There is no other human activity that we "teach" in quite the same manner. A child's first lesson in sex is generally that there is something out there that adults don't want them to know anything about. Then, one day, probably by the time they've finally put the jigsaw together, someone comes along and gives them the official version of what's going on on the other side of the "parental control wall" or after the watershed, and tells them how risky it is. If I were a child I would be having none of it.

But I am not suggesting we should remove sex from the curriculum altogether – in fact, we need more of it, sprinkled throughout other lessons in a way that makes sex seem like a normal part of discussable life. And we need to access it, not just through biology books, but literature – since it's only there that the wider implications and rollercoaster feelings attached to sex are tackled and reflected. That is the place where we see sex from all angles, where the missing links between the heady intoxication of lust, the pain of rejection and the confusions of pregnancy are explored.

Frank Furedi, a long-term crusader against the current moral panic over child sexuality, has written: "The agenda of the sex-education industry seems to be to kill passion and transform pleasure into a banal and very safe experience."

This has been true for some time. My own mother did a rather brilliant job of conveying the full scientific facts of sex to me and my four brothers from a very young age. Once, while we were sitting round the breakfast table, she asked how we were all going to stop ourselves from getting Aids. My youngest brother, then four, piped up: "Use a condom!"

Yet what I think she never managed to convey to me was how over-powering, confusing and wonderful sex might be. For this, my guides were mostly literature, from the photo-story girl magazines I consumed avidly, through to the copy of Lace I found beside my grandmother's bed.

We must be honest about the cause of higher rates of sexual activity and continuing teenage pregnancy levels today, and it is not a lack of education. Rather, it is a combination of factors including the lack of opportunities associated with deprivation, an absence of moral opprobrium, and our own coy-but-liberal attitudes as adults.

But also we must remember that much as we might treat teenage pregnancy with alarm, actually, sex is not as perilous as it once was. The course of a woman's life – whether she marries, if she can get a job – is rarely dictated by a moment of conception.

Meanwhile, what is rarely mentioned is that the young might really be pursuing that lost risk and danger. According to the "risk compensation" theory, the more we try to make dangerous activities safer, the more individuals will look for ways to push further into a risk zone.

We invented safety belts, and people became less cautious on the roads. We created anti-lock brakes, and they began to drive more closely to the car in front. And perhaps, too, you could say we invented effective contraception, and people still found ways of having a sexual life that was risky. Indeed, perhaps our whole culture of high sexual activity is driven as much by an urge to take risks as by lust. It's just a theory. But if it's true, there's no way we will ever "educate" our children into a culture of safe sex. That doesn't, however, mean we shouldn't talk about it.