The outcome of the 1948 U.S. Supreme Court case McCollum v. Board of Education, specifically stated that state schools teaching matters related to religion is an infringement of the concept known as "separation of church and state." This interpretation of the law has caused much conflict and confusion in the decades since. The same liberty that allows one child to participate freely in a religion also protects another child from being indoctrinated into any religion. This means the pro for one argument is actually the con for the opposing position, and vice versa.
Teaching about various religions in state school offers the opportunity to expose children to a variety of different faiths, and cultures, which is a pro. The other side of that coin is that teaching children about other religions or denominations can be considered indoctrination, as the line between teaching and preaching might prove too thin for some parents. Potentially, this could infringe on individual liberty, which is a definite con.
Teaching vs Indoctrination
In 2009, the Lantern Road Elementary school in Fishers, Indiana, stirred controversy by teaching second graders a song that included the lyric, "Allah is God." School officials said it was an attempt to teach students about corresponding holidays from other faiths -- including Ramadan, Hanukkah and Kwanzaa -- during the Christmas holiday season. This is both a pro and a con in the debate given the fundamental differences that separate the religions involved. Many Christian parents where upset to learn their children were being taught a song that suggested something contrary to their faith. Ultimately, the lyric was removed from the school program.
A Time and Place
Thomas Jefferson introduced the concept of a "wall" between church in state in a letter to the Danbury Baptists. In it, he stated, "religion is a matter which lies solely between Man & his God." The Court's decision in the aforementioned McCollum v. Board of Education agreed. Though that specific case involved voluntary religious classes being taught with the consent of parents, the Court ultimately ruled that state school was not a proper venue for such sensitive instruction, which according to the Constitution demands neutrality. Churches, which are not under the same jurisdiction as state schools, have the freedom to teach religion on a level more consistent with the individual beliefs of the family.
The Continuing Conflict
The Supreme Court has consistently ruled that the government must remain neutral on matters of religion, showing no hostility or favour toward any one doctrine. This holds true to the first amendment of the constitution, which states, "Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof." However, policies that prohibit prayer in school, or favour evolution over the religious doctrine of creationism, are often an affront to those who hold those beliefs dear. Arguments can be made that these policies are in fact an infringement on religious freedom. The arguments for or against religious instruction in state schools essentially boil down to an interpretation of the law based on personal perspective.