I have come to realize that you can't really teach someone abstinence. That is, you can teach all you want about the concept of abstinence, but it requires a great deal of conviction and personal resolve to maintain that position. There seems to be a disconnect between the biblical teaching about the place of sex and the reasons behind the teaching.
Like others who have already posted responses, I agree the goal of abstinence education is slightly different than the goal of sex education. It is almost as if abstinence education focuses on the “before” and sex education focuses on the “during/after.”
Perhaps a comprehensive sex education program should include a discussion of abstinence. Some, in fact, do include discussions of abstinence, but it seems that sometimes the abstinence talk doesn't receive much credibility, and although it might be touted as the only truly safe and foolproof option, many people approach it as something that no one ever practices. The truth is, if 80 percent of evangelicals have engaged in premarital sex, that still leaves 20 percent who practice abstinence. Statistically speaking, then, abstinence is not an unattainable goal. It is just a great deal more difficult, especially if a person doesn't really buy the abstinence argument.