What could possibly be the connection between school desegregation and the mystifying phrase "Bong Hits 4 Jesus?" Something critically important, it turns out. Both have spurred legal battles that have risen to the U.S. Supreme Court, and both demonstrate that a public school system that demands everyone's support but can only reflect some people's values will inevitably lead to conflict.

In mid-December, the Court heard arguments on school integration cases from Seattle and Louisville, Ky., in which plaintiffs challenge enrollment policies that consider race in deciding who can attend specific public schools.

Seattle's system considered race in determining who could attend high schools to which more students applied than could be accommodated. (The district suspended use of race when it was challenged in 2001.) If a child's race would have gotten a school closer to an enrollment mix of 40 percent white and 60 percent minority - roughly the district's overall complexion - the child got an admissions advantage.

In Jefferson County, Ky. - which contains Louisville - parents are allowed to choose among many district schools, but no school's enrollment can be less than 15 percent, or more than 50 percent, African American. The result: students have been denied admission to the schools of their choice on the basis of their race.

The desire to promote integration and diversity is laudable. Indeed, because Seattle and Jefferson County public schools are government entities, they have an obligation to ensure that benefits are distributed equally. But that's also the integration plans' biggest failure: Rather than letting all parents choose the best schools for their children, the districts have kept kids out of good schools because of their race.

As Louisville mother Tamila Glenn, whose son was forced to change schools between kindergarten and first grade, put it: "It's like saying (to your child), 'You can only play with these people because you have too many black friends.'"

So how does the bong hits case, which the Court agreed to hear last week, pit irreconcilable values against each other as the integration controversies do?

It goes back to January 2002, when Juneau-Douglas High School student Joseph Frederick held up a sign emblazoned with "Bong Hits 4 Jesus" as the Olympic torch passed through Juneau, Alaska. Frederick refused to put the sign down when principal Deborah Morse ordered him to, so Morse suspended him, asserting that she could not allow a student to encourage illegal drug use and defy her instructions.

Because citizens have a right to expect that the schools for which they pay won't permit behavior that disrupts learning, or promotes illegal activity, Morse did what she had to. But then there are those pesky competing values again: While districts must maintain order, government may not punish speech just because some people find it inappropriate.

"We thought we had a free-speech right to display a humorous saying," Frederick has explained.

Unfortunately, while Frederick's sign might have been unique (though not, frankly, all that funny), neither the fight over it, nor the Seattle and Louisville cases, is the least bit novel. The sad reality is that public schooling forces Americans to fight constant, values-laden battles not just over race or free speech, but a myriad of other issues as well, including sex education, religious expression, homosexuality, evolution, and so on. And brace yourselves, because the Christmas season sparks some of the fiercest battles of all.

These conflicts are inevitable: No school can simultaneously respect all speech and censor disruptive expression; engineer integration and be colorblind; celebrate Christmas and be totally secular; and so on. As a result, citizens have no choice but to engage in political combat to get what they want from the schools they are forced to fund.

Thankfully, since these battles have a common cause, they also have a common solution: Unfettered school choice, in which the public ensures that everyone can afford an education, but individual parents and autonomous schools decide what values they'll embrace.

Want a racially diverse student body, as many parents, both black and white, do? Pick a school that has one. Not fond of kids talking up bongs? Choose a private institution where children check their speech rights at the door. Want to end the fighting? Let parents select the schools they like, and the underlying cause of combat will disappear.

Whether it's an issue as contentious as race, or as strange as a kid's sign about bongs, public education is beset by constant political warfare. But it doesn't have to be. All we need to do is set people free.

Neal McCluskey is an education policy analyst at the Cato Institute's Center for Educational Freedom, and author of the upcoming Cato study "Why We Fight: How Public Schools Create Social Conflict."