All of the talk in the news about federally funded abstinence programs making false claims to children made me remember the D.A.R.E. program. I remember very clearly a police officer telling our class that smoking marijuana just once could kill a person. Even at the tender age of 10, I knew he was full of crap.
So instead of being so scared that I never smoked weed, I completely disregarded everything that he told us, most of which was probably true and helpful for kids.
I had my first puff of that happy stuff when I was eleven.
I think quite a few of the people I smoked with in later years are now pretty screwed up. So there is definitely some sense in telling kids to stay away from it. But a lot of them aren't screwed up at all, and even the ones who are have other predominant contributing factors (often weak families). It seems like about half of the kids I went to highschool with smoked pot at least once. Some, like me, don't smoke at all anymore.
The fact is, kids can tell a lot of the time when they're being lied to, and they're not very likely going to take a lier seriously, even if he has good things to say overall.