New York’s public-school principals have generally felt it their duty to protect, not strain, relations between their schools and the DOE bosses at Tweed. Accordingly, principals have mostly not been among the critics of the system’s growing emphasis on standardized testing. But this year, a small group of them began to speak out. Among the dissidents: Zipporiah Mills of P.S. 261 in Boerum Hill, who’s refused to have her diverse school branded a C, no matter what its last two progress reports from the city might indicate. “No one knows that our kindergartners are taking Arabic classes or that we have Carmelo the Science Fellow [a renowned teacher]. No one knows that because all anyone sees is the C,” she says. In April, Mills permitted anti-testing activists to speak at her school and then later film a video titled “I Could Have Been.” In it, students state what they might have been doing had they not been drilling for exams. “Writing my latest masterpiece,” says one. “Reading my favorite book,” says another. Those are the kinds of things classrooms are really for, says Mills. “We didn’t get into education,” she says, “to be the givers of tests.