Just because you don't see it, it might still be there. The gay proponents are pretty creative at getting their message in schools. Teacher Unions have been very cooperative with the gay movement. Fighting vouchers might be the teacher unions biggest effort, but pushing the gay agenda is easily number 2.
Again, I don't know where you're writing from, or what age your kids are, but I've had kids in liberal Baltimore County public schools every year since 1988 (23, 19 and 13 year old kids), and I can tell you this, pushing the gay agenda hasn't even gotten into the top 10 things they are pushing.
I obviously know nothing about you, but I've had freepmail conversations with folks espousing the same side of the issue as you who have never had kids in public school. That points to a bit of a credibility issue.
I'd say there are quite a few folks with agendas on both sides of this coin.