This is the kind of reasoning the right-wing fundamentalists do (if it can be called reasoning at all). They are terrified that teaching high school students the truth about sex (and contraceptives) will make them want to run out and have sex. It's like they think sex is some kind of great secret that kids won't know about until they turn 18 or maybe 21 -- when I guess they magically will know about it then. They don't seem to realize that most kids know all about sex in junior high (although most wait before engaging in it).
But when it comes to guns, a much more dangerous thing (which can end their lives instead of just messing with their future), they have no problem with teach even elementary school kids how to shoot. Of course, this whole concept is illogical. If teaching a kid about safe sex will make him/her want to engage in sex, then why doesn't teaching a kid about guns make them want to go out and shoot someone. Could it be that kids are much smarter than fundies give them credit for -- maybe even smarter than the fundies who want to keep secrets from them?