Nothing new here, really.
Religious content was banned from school graduations by the U.S. Supreme Court back in 1992, when "School principals in the public school system of the city of Providence, Rhode Island, invite[d] members of the clergy to offer invocation and benediction prayers as part of the formal graduation ceremonies for middle schools and for high schools."
What's wrong with prayer at a graduation ceremony? Nothing. Let's review.
The First Amendment:
Congress shall make no law respecting the establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances.
By "Congress" the Framers certainly included the Executive and Judicial Branches. (Actually, it never occurred to the Framers that the Judicial Branch would make laws -- that power was given only to Congress. But if the First Amendment prohibits Congress from making certain laws, it certainly was intended to prohibit those branches which have no legitimate law-making powers at all from making a law.)
What is a law "respecting an establishment of religion?" A federal law establishing the Anglican Church as the official state church of the United States would be such a law. A federal law requiring the establishment of the Anglican Church as the official state church of Pennsylvania -- when Pennsylvania had already made the Quaker religion the official state church -- would also be such a prohibited law. An attempt by the federal government to prohibit Pennsylvania from making the Quaker religion the official state church of Pennsylvania would be a violation of the First Amendment's "establishment clause."
The states demanded the Bill of Rights as an amendment to the federal Constitution because they wanted assurances that the new federal government wouldn't be messing around with the way the states dealt with religious matters in their own state.
The Framers of the Constitution felt no need to include in the original document a provision expressly upholding a general theory of freedom of speech, undoubtedly holding to the belief that the government they envisioned, limited to the enumerated powers, could not constitutionally enact a law in derogation of the principle of free speech. Popular pressure, however, demanded a more articulate expression of the guarantees of individual rights from governmental interference.
Nowak, Rotunda, and Young, Constitutional Law, 833, (1986). See also Pfeffer, Church State and Freedom, 126 (1967) ("The 'public clamor' for a bill of rights was so great that Madison and the other proponents of the Constitution could persuade several states to ratify only after promising to work for the addition of a bill of rights."), and J. Rutledge, dissenting in Everson v. Board of Education of Ewing Tp., 330 U.S. 1 at 39, 67 S.Ct. 504 at 522-23 ("[Madison] pledged that he would work for a Bill of Rights, including a specific guarantee of religious freedom, and Virginia, with other states, ratified the Constitution on this assurance [note omitted].").
The federal Constitution simply would not have been ratified if the states knew that the newly-created federal government would have the power to ban prayer from high school graduation ceremonies throughout the various states.This is a no-brainer.
In 2000, the federal court went beyond the case of school officials planning a prayer ("establishment"). The Court went after "free exercise." Voluntary prayer before a high school football game by a student chosen by other students in a school election was banned. The Court upheld the ruling of the Court of Appeals which said, "Regardless of whether the prayers are selected by vote or spontaneously initiated at these frequently-recurring, informal, school-sponsored events, school officials are present and have the authority to stop the prayers."
In other words, if the government school officials ask a clergyman to say a bland non-denominational vaguely theistic prayer at graduation, that's an "establishment of religion." But if a students seeks to exercise her First Amendment right to free speech and the free exercise of religion and the government school officials permit it, then they have created "an establishment of religion."
The new rule appears to be: If a school official sees that the free exercise of religion is about to take place and does not actively intervene to stop it, the school is guilty of "establishing a religion."
None of this nonsense would have been tolerated by Americans in 1776. If Parliament or King George III had passed similar edicts, the American Revolution would have resulted even if there had been negligible taxation with perfect representation.