Quote from the link in OP
"As well as warning pupils about the risks of sex, lessons should also inform older pupils about sexual pleasure and how to achieve it for both themselves and a partner, with the aim of helping them secure mutual sexual happiness"
That sexual pleasure for both partners - within a setting of mutual consent, respect, liking for one another and the absence of coercion of any sort - is the aim of having sex should be made clear. As the TED video upthread makes clear, there are far too many young women who think sex is about "giving him what he wants, or part of what he wants, to make him stay with you/get him out the door" (delete according to circumstances).
But I think bring the how into the classroom is wide-open to abuse - a tiny, but non-negligible minority of creepy teachers using it as a springboard for abuse, peer-on-peer abuse and humiliation in the class room - so many places this could go horribly wrong.