As a teacher in Oakland, Calif., Kareem Weaver helped struggling fourth- and fifth-grade kids learn to read by using a very structured, phonics-based reading curriculum called Open Court. It worked for the students, but not so much for the teachers. “For seven years in a row, Oakland was the fastest-gaining urban district in California for reading,” recalls Weaver. “And we hated it.” The teachers felt like curriculum robots—and pushed back. “This seems dehumanizing, this is colonizing, this is the man telling us what to do,” says Weaver, describing their response to the approach. “So we fought tooth and nail as...