Did the first 4, then skipped to the answers - and I got all of those right! Well, with the exception of DARE; I see no logical way it can't be harmful and counterproductive - for the simple reason that it's crying wolf to teenagers, who are both impressionable and suspicious of adult authority.

I think that, when programs like these are unleashed upon sheltered teenagers from middle-class backgrounds (which is now happening in Russia as well), it can be a big part of the problem; kids are told in strong terms that marijuana and meth are both deadly and awful. Then they personally see drug users who are functioning people (which are probably the majority), and apply reversed stupidity to conclude that adults just hate fun, and that hard drugs must be an excellent idea. My BF got an article published on this very issue, actually.

P.S.: check out another article, published in a very unexpected venue. Apparently, people who have some good sense and aren't in underclass conditions might not suffer badly from heavy lifelong drug use.