As much as I disagree with teaching children that a specific religion is correct (as opposed to telling them what the various religions believe in a kind of comparative religion way), I do not believe that the state has the power to tell people how to raise their children. There are clear exceptions to this, I know - you have to raise your children within the bounds of the law. But in the US, the free exercise clause means just that - you are able to do your religious thing (provided you don't hurt anybody) without state interference. Secularism cuts both ways I think - separation of church and state keeps BOTH out of each other's hair