SANTA ROSA, Calif. — When a few classmates razzed Rebekah Rice about her Mormon upbringing with questions such as, "Do you have 10 moms?" she shot back: "That's so gay."

Those three words landed the high school freshman in the principal's office and resulted in a lawsuit that raises this question: When do playground insults used every day all over America cross the line into hate speech that must be stamped out?

After Rice got a warning and a notation in her file, her parents sued, claiming officials at Santa Rosa's Maria Carillo High violated their daughter's First Amendment rights when they disciplined her for uttering a phrase "which enjoys widespread currency in youth culture," according to court documents.

Testifying last week about the 2002 incident, Rice, now 18, said that when she uttered those words, she was not referring to anyone's sexual orientation. She said the phrase meant: "That's so stupid, that's so silly, that's so dumb."

But school officials say they took a strict stand against the putdown after two boys were paid to beat up a gay student the year before.

"The district has a statutory duty to protect gay students from harassment," the district's lawyers argued in a legal brief. "In furtherance of this goal, prohibition of the phrase 'That's so gay' ... was a reasonable regulation."

Superior Court Judge Elaine Rushing plans to issue a ruling in the non-jury trial after final written arguments are submitted in April. Her gag order prevents the two sides from discussing the case.

Derogatory terms for homosexuality have long been used as insults. But the landscape has become confusing in recent years as minority groups have tried to reclaim terms like "queer" and the n-word.

In recent years, gay rights advocates and educators have tried teaching students that it is hurtful to use the word "gay" as an all-purpose term for something disagreeable. At Berkeley High School, a gay student club passed out buttons with the words "That's so gay" crossed out to get their classmates to stop using them.

Rick Ayers, a retired teacher who helped compile and publish the "Berkeley High School Slang Dictionary," a compendium of trendy teen talk circa 2001, said educating students about offensive language is preferable to policing their speech.

"I wouldn't be surprised if this girl didn't even know the origin of that term," he said. "The kids who get caught saying it will claim it's been decontextualized, but others will say, 'No, you know what that means.' It's quite talked about."