Right. Because if you ignore the existence of gay people, and their consequent right not to be, say, bludgeoned to death by assholes like you, we're doing the only responsable thing?
Here's a thought: Some of those kids you're seeking to "protect" are going to be gay. Just how it is. And those kids are going to grow up terrified, with no one to confide in. Do you remember how bad it was to experience puberty in general? Now imagine you can't speak honestly with anyone, not a friend, not a parent, not an older brother or sister, NO ONE.
Shouldn't the school, at least, be a place of relative refuge? Shouldn't teachers make it clear they're available to talk with and be confided in by students in a very difficult time? GLBT teens are multiple times more likely to kill themselves than straight teens are, and I think that's enough on it's own to justify talk of tolerance.
Tolerance won't make their straight peers gay. No one thinks "hey, I shouldn't hate my gay friend" and then immediately leaps from there to "I should suck his cock sometime. Maybe that'd be fun." If you're attracted to males, you're attracted to males, and that's how it is. No woman can walk up and say "come with me" and all the sudden, you feel yourself weak in the knees around women. Ditto in reverse.
Tolerance may, however, keep straight kids from harrassing or beating up gay kids, and keep teachers able to provide a secure learning environment so that gay kids have the same access to education that straight kids have.