Assigned to draw a landscape, a senior at Tomah High School in Tomah, Wis., drew a path surrounded by mountains and clouds leading to a cross. At the top of the picture, he put the words “John 3:16 A sign of love.”

Most public school art teachers I know would accept the drawing, evaluate the technique, and put it on the wall with other student artwork.

Instead, the teacher at Tomah High told the student (identified as A.P. in court documents) to remove the religious reference, claiming that it infringed upon the rights of other students. When A.P. refused, the teacher showed him a school policy that prohibits art projects depicting “violence, blood, sexual connotations, [or] religious beliefs.”

A.P. calmly tore the policy in half and was promptly thrown out of class. For ripping up the policy, the student got detention. For his drawing, he got a zero. A second art teacher subsequently refused to allow A.P. to make a metal cross to fulfill an extra-credit assignment permitting students to make a metal object of their choosing.

Two weeks ago, A.P. filed a federal lawsuit challenging the constitutionality of the school’s “art project” policy. It should be an easy case.

Beyond the outrageous and offensive lumping of religious beliefs with violence, blood and sex as forbidden topics, the Tomah High policy completely ignores the First Amendment. Under current law, as the U.S. Department of Education guidelines explain, “Students may express their beliefs about religion in homework, artwork, and other written and oral assignments free from discrimination based on the religious content of their submissions.”

A.P. may flunk art, but he should get high marks in civics — he knows an unconstitutional policy when he sees one. School officials in his district, however, need a refresher course in religious liberty and free speech.

Public school advocates (and I am one) may be tempted to write this off as an isolated incident, one school’s misreading of the First Amendment. That would be a big mistake.

It’s true that policies like the one at Tomah High are rare — few public schools are overtly antagonistic toward religion. It’s also true that a growing number of school districts are becoming proactive on religious-liberty issues, developing constitutional policies and practices.

Richardson, Texas, to cite one of many good examples, has a Religious Practices Advisory Committee of parents, community leaders and educators working together to uphold the First Amendment in their schools.

But many other districts — perhaps the majority — have few sound policies on religion (or, if they have policies, no one knows about them). When a question arises about student religious expression, these schools sometimes overreact by censoring the speech.

You may recall the Colorado student who got into trouble last year for mentioning Jesus in her graduation speech. Or the New York fourth-grader who was prohibited from giving religious messages to her classmates. Or the student in Texas who was barred from distributing Valentine’s Day cards with a religious message. The courts have already handed victories to the latter two – and the first will likely win her case as well.

Wasteful, divisive and unnecessary lawsuits like these can be avoided, but only if administrators and school boards start paying attention to the First Amendment.

As I see it (in my frequent visits to public schools), the problem isn’t public school hostility to religion. The problem is ignorance of the law combined with a fundamental confusion about the “critical difference between government speech endorsing religion, which the Establishment Clause forbids, and private speech endorsing religion, which the Free Speech and Free Exercise Clauses protect” — to quote the U.S. Supreme Court’s ruling in Westside Community Board of Education v. Mergens.

A.P., in other words, is not the government. As long as he otherwise fulfills the school assignment, he’s free to express his views about his faith.

This story, like every “bad story” about school violations of the First Amendment, will help fuel efforts by opponents of public education to characterize all public schools as hostile to religion.

Such sweeping generalizations are unfair. But if school officials are tired of being under fire, they should stop providing the ammunition.

Charles C. Haynes is senior scholar at the First Amendment Center, 555 Pennsylvania Ave., N.W., Washington, D.C. 20001. Web: firstamendmentcenter.org. E-mail: chaynes@freedomforum.org.