The way Bart Simpson would see it, Jamie Brown was having a cow. Brown, the principal of the Cambridge Elementary School in Orange, Calif., was confronted at a recent recess with one of the most potent forces in American society: a Bart Simpson T-shirt (one of an estimated 15 million Simpson family shirts sold) worn by fifth-grader Alex Romero, 11. Above the image of the subversive, spike-headed urchin from Fox's TV hit The Simpsons appeared the words: "I'm Bart Simpson. Who the hell are you?"

Brown was not amused. He approached Alex and asked him not to wear the shirt again. The youngster politely complied. Brown permitted the innocuous Bartman shirt to be worn in school but banned another Bart model reading, UNDERACHIEVER AND PROUD OF IT, MAN.

Aye, caramba! Is this the beginning of a Bartlash? (The Underachiever T-shirts have also been nixed at five schools in Fremont, Ohio.) "I'm certainly not on any campaign," insists Brown, 39. But, he adds, "For a child to wear a T-shirt with the word hell on it—that's not exactly the type of behavior we hope elementary schools model. And I don't want kids even thinking being an underachiever is cool." The reaction from parents, he says, "has been almost 100 percent positive."

Not quite, dude. Says Jeanette Manning, 31, whose 12-year-old son, Chris, is a sixth-grader at Cambridge: "I almost went out and bought Chris [an underachiever shirt] just on principle." And Alex Romero's mother, Maira, 39, declares: "I'd much rather have him wearing a Bart Simpson [shirt] than one of those rock and roll T-shirts with the skull-and-crossbones on it."

But authority figures everywhere, beware: There's potential for a major cow when a talking Bart Simpson doll arrives on the market in August. Watch out, dudes!