Rabbi Shmuel Poppenheim of Edah Haredit, oft quoted in Gil Zohar's wonderful piece on haredi violence aimed at stopping Jerusalem's Gay Pride parade, notes:
"Of course we don't talk about the thing itself. Nobody will tell his son exactly what it is. We talk about a parade of immorality, abomination. Nobody says that it's people walking naked in these parades or talks about what exactly they do. There are people, even 50 year-olds, who are under arrest after demonstrating, and don't understand exactly what it is. Children do ask, but we think that this world is full of immorality in any case. Our children will find out about these concepts one way or another, so it's better for them to find out about it through condemnation and protest, through a position of extremism, through a war against it - not through lust."
Or perhaps they will find out about truly abnormal sexual behavior the way most haredi children do – in a mikva or a yeshiva dormitory.