Why?
Many decent people don't like kids being taught in school that this is normal or acceptable. The schools should not be indoctrinating our kids. Someone wants to be gay.
1. Sounds like these parents aren't so decent after all, as this teaches intolerance. Many "decent" people didn't want their pure white children being taught alongside filthy blacks. Ignorance is ignorance.
2. The schools should teach facts. Scientific evidence suggests that homosexuality is of biological doing. It's displayed in the animal world across the majority of species. Before you use the argument that, "Well animals don't have a conscious, so that doesn't count!", science evidence also suggests that animals do, in fact, possess consciousness. Church is where children get indoctrinated to hate anyone who is different than themselves.
3. Touching on #2, it is not a choice. Why would anyone CHOOSE to be a minority known for discrimination, social torment, bullying, assault, and brutal murder? Did you choose to be straight? Choose to find another man sexually and emotionally attractive. You can't, can you? Try as hard as you can and it won't work, assuming you're a heterosexual. Maybe then you will realize how it's just as impossible for a gay man to find a woman sexually and emotionally attractive.
Libertarian my straight white ass.