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The start of a new school year always brings change. For students, it’s new classmates, new teachers and new lessons. For culture warriors, it’s a new front in the long-running battle over school prayer and religious proselytizing. On one side, civil libertarians charge that schools imposing mandatory prayer on students are in violation of the Constitution. On the other, religious groups argue that it is faith that is being discriminated against — and in several states, religious groups have been notching some big victories.

In Missouri, voters this month overwhelmingly passed Amendment 2, a so-called right-to-pray amendment, which, among other things, asserts “that school children have the right to pray and acknowledge God voluntarily in their schools.” Critics are more worried about a clause that also protects the right of students to opt out of academic assignments that violate their religious beliefs. While it’s easy to see the appeal of the amendment — no parent would want schools to teach their children values with which they disagree — the law is worded so broadly that it could interfere with schools’ ability to teach evolution, critics say, or even women’s rights or the value of tolerance for other religions.

In April, Tennessee enacted a law — dubbed the monkey bill — that protects the right of teachers to teach creationism rather than evolution. Louisiana had already adopted a similar law, and other states are weighing doing the same.

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Meanwhile, the civil libertarians are waging their own battle. This year marks the 50th anniversary of Engel v. Vitale, a broad, landmark Supreme Court ruling that found that the First Amendment bars public schools from imposing prayer on students. The American Civil Liberties Union (ACLU) has been calling out perceived backsliding among school districts hoping to find ways around Engel v. Vitale for years, and right now it’s focusing on South Carolina.

Last week the ACLU launched a campaign called “Religious Freedom Goes to School,” aimed at bringing the state’s schools into compliance with the First Amendment. “We are challenging all of South Carolina’s public schools to do more to protect religious freedom,” the group says on its website, “because all students, regardless of faith or belief system, should feel safe and welcome in our public schools.”

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The ACLU says it has received complaints from across South Carolina of teachers leading prayers in class, Bibles being distributed in schools and coaches holding prayer sessions at football practice. The group sued one South Carolina school district last year on behalf of a student and his father, who claimed they were ostracized after objecting to religious activities at the child’s middle school. These included being required to attend “worship rallies” (featuring a performance by B-SHOC, a Christian rapper who sings songs like “Crazy ‘Bout God”) and to sign pledges dedicating their lives to Jesus. The school district signed a consent decree agreeing not to engage in improper religious activity in the future.

In Georgia, a group called the Freedom from Religion Foundation has charged that a high school football coach has been holding pregame meals in a local church, where the students are preached to by a Christian minister; leading pregame and postgame prayers; and pressuring students to attend a Christian football camp.

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These battles are hardly surprising. The nation is deeply divided on social issues of all kinds, including the role of religion in public life. But despite the current skirmishes, the real story is how far the nation has come in establishing a wall of separation between religion and public schools.

In Engel v. Vitale, the 1962 Supreme Court case, a group of public-school parents challenged a New York school district’s requirement that every class begin the day with an official prayer thanking “Almighty God.” It is a sign of how far the debate has shifted that today this sort of officially mandated daily prayer in public school classrooms would feel like a relic from another century.

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