We ask a great deal of schools. When any social problem arises we will agree the solution lies in education, which usually means schools. Where sex is concerned, we need to ask much more of them.
Incidents such as the recent "Roast Busters" case show that sex education these days needs to be more than a component of the health and physical education curriculum. Children at puberty are being exposed to a sexual environment their parents hardly imagined at the same age. Today's music videos, internet porn and teenage social pressure can create unreal and damaging misconceptions of sexuality in an immature mind.
Schools need to put sex into a context of healthy relationships and mutual respect. Parents need to talk about it with their adolescent children in the same way, of course, but not all will manage to do it. We have to look to schools to ensure all youngsters are offered a healthy, non-threatening forum for discussion.
Some already do so, by subscribing to programmes such as the one offered by Rape Prevention Education. But overall, sexuality education is variable. Parliament's health select committee has described it as "fragmented" and "uneven". No wonder, since schools are obliged to consult parents about the nature of the programmes they offer.
The Ministry of Education says it is updating guidelines for schools in response to the select committee findings but its deputy secretary of student achievement, Dr Graham Stoop, says it will not be recommending when or how sexuality is taught either in primary or secondary schools, "as schools make these decisions in consultation".
Its minister, Hekia Parata, should invite the officials to be bolder. The argument of yesteryear has been overtaken by the main concern today. The need to understand consent bridges the old divide between those who wanted sex education strictly confined to physical and biological advice, and those who believed morally neutral programmes endorsed premature activity.
The need today is to stress that "no" means no, reluctance means no, even uncertainty means no.
Consent, as an educator put it, is a "mutual, enthusiastic yes". If that is understood by young people, along with respect for those who respect themselves, it will be an antidote to the misinformation around them.
They need to know that honest, respectful, loving sex is infinitely better than anything they can see on screen, and well worth their wait.