Although the suggested activities for Mix It Up at Lunch Day do not expressly address gay and lesbian students, the law center itself promotes equal treatment for gays and lesbians and that philosophy then informs the school program, he said.

“Anti-bullying legislation is exactly the same,” Mr. Fischer said. “It’s just another thinly veiled attempt to promote the homosexual agenda. No one is in favor of anyone getting bullied for any reason, but these anti-bullying policies become a mechanism for punishing Christian students who believe that homosexual behavior is not something that should be normalized.”

The program is not about sexual orientation but rather about breaking up social cliques, which are especially evident in a school cafeteria, Ms. Costello said.

In some schools, cliques are socioeconomic. In others they are ethnic or religious or based on sexual orientation. By giving students a way to mix with other students, self-imposed social barriers can be broken down and bullying can be curbed, she said.

“Many of the targets of bullying are kids who are either gay or are perceived as gay,” she said.

But the idea that the program is intended as homosexual indoctrination is simply wrong, Ms. Costello added.

“We’ve become used to the idea of lunatic fringe attacks,” she said, “but this one was complete misrepresentation.”

Parents who are on the American Family Association e-mail list were encouraged to keep their children home on that day and to call school administrators to tell them why.