Public schools in my area are rather horribly underfunded, and the parents have more say in thier children's educations than may necissarily be a good idea. For instance, we never learned about birth control in school- in fact, we were told that if we had sex we would get an STD and die (unless we were married, in which case I'm guessing STDs didn't work anymore or something ).
Needless to say, we had such a high teen pregnancy rate that the New York Times ran an article on our school's large number of knocked up teens.
Though parents may think that it's a good idea to have a lot of say in what the school teaches, it's not always best for the kids. None of those girls or thier baby daddies ended up going to college, and almost all of them are working low wage jobs in a nearby town.
Just something to think about on that argument