Real problem, wrong approach
On the one hand, I don't want to give the impression this isn't serious, it can be very bad. As another comment pointed out, it often involves blackmail. The basic scenario is a seemingly harmless online version of the "show me yours. I'll show you mine" game suddenly turns deadly serious when the other person threatens to show the picture to "everybody" unless their demands are met. Unsurprisingly those demands often involve creating even most explicit pictures, so cooperating isn't likely to end well.
But on the other hand, talking about this breathlessly in vague terms peppered with think-of-the-children-isms serves nobody, except maybe the child safety charities. It mostly involves teens, so paedophiles (in the proper sense of the term) have little to do with it. In fact the abuser could quite easily be a peer, perhaps just a bit older. The efforts of well-meaning parents and others can even backfire if they don't understand the real situation. If all they do is hammer home the "don't be naughty on the internet" point, that actually adds strength to the threat, since the prospect of parents finding out is one of the scariest parts of such blackmail.
Certainly young people should be warned about this danger, but they also need to feel like they can talk to their parents freely about any trouble they get in online, no matter what.
Biting the hand that feeds IT
