Well I think it is something thaty a teenager should be answering aswell 'cause it is still a two sided story here, and that a reply by a teenager will give you insite in why they look at it.
Unlike children only condemming it and punnishing it maybe will NOT work. That has to do with the nature of teenagers. Teenagers are in general somewhat rebellious towards authority because they are inventing themselves.
I myself wouldn't be as worried about the porn, I know from personal and my friends experience that looking at porn is not as much about the sex but much more about curiosity about what sex can be. What you should talk to them about it and make sure they keep perspective and know it is a film made to generate sales (like you make sure they know that an action movie is cool onscreen but you shouldn't walk into a building and kill every one there.)
Then when you talk about it make sure you speak to them as equals as adults, even though they are not it will prevent the "I hate authority" mechanism to kick in.
Also keep in mind that if you take the porn away you won't take away their thought and more inportantly their friends. I know for sure that many boys who have an internet connection will at one time have looked at porn out of curiosity, at school we talked about it quite a number of times.
And if their interrest will shift towards (BD)SM it will probably where there interrests lie not because they have seen porn. I for one like redheads more then other haircollors that doesn't mean I have seen only movies with red-heads in them. And even if they look at BDSM that doesn't mean they will want it themselves, porn can be the visiualization of a "dark" fantasy you wouldn't dare dreaming of acting out for real.
And I'll make it more shocking, children as young as 10y old will talk about sex with their friends, not about having it but more in the likes of YOU SAID BL*WJ*B!! gighel gighel they will not know what most of those words will mean but the'll use em anyway.
That means that sex education has to start not later then twelve because it is much easier to write on a clean sheet of paper then a full one. And remember that the smallest gestures can make a profound impact, I remember that when my dad talked about sex with me he closed the curtains, for him it was because it was getting dark my interpretation at the time was on the other hand that it was something that you shouldn't be seen talking about. And it made a profound impact 'cause it is the only thing I can remember from that conversation.
Remember also that you shouldn't only tell the nagative sides of sex! CHILDREN ARE NOT STUPID!!! They know that there is a multi billion dollar porn industry and know that if sex only had negative sides to it that there wouldn't be a porn industry at all. So also talk about the positive sides of sex and of course don't forget to talk about the condom (and the pill for girls better to safe then sorry) This will also take out the being bad if you have sex side because if you're a teenager bad often equals cool.
Also remember that the age on which teens have sex for the first time is 16,9 years in the US (study by durex 2004) so the 16y old is actually at the age of having sex be glad he's only looking at it. And hey perhaps he even learns from it (how to keep it interresting for instance) in a recent television show in the Neterlands in which teens (though the teens came not from the Netherlands originally) said they looked at porn just to learn new positions and so.
I know that it isn't what you want to hear but it is the truth, sex is just a part of growing up and porn just fufills the teens needs to be educated about the subject.
