From what I've heard, middle school aged kids aren't having intercourse in large numbers, but oral (this was from a Globe and Mail article from a while back, which I don't have the link for. I do, however, have the link to a similar article from my high school's newspaper:
http://www.thespectrum.ca/issue6comment5.htm) . Part of the problem, I think, is that sex ed doesn't teach much about anything other than intercourse, so kids really aren't all that informed. One sad thing, I think, about Canadian schools and our forms of sex ed is that abstinence isn't really taught at all. I remember nothing about a "stay away from sex" option during frosh week. I confronted my frosh leaders and dons (RAs) about that, and they really weren't able to give me an answer. Maybe it's just another sad fact about liberal values.