In this article, the author examines successful schools with high concentrations of poor and minority children--those in which students were doing as well as or better than those in affluent schools on statewide standardized tests--to see what they were doing to improve the level of instruction in their classrooms. These high-performing, high-poverty schools were not just different in degree from other schools, they were different in kind. School leaders had clearly articulated expectations for student learning, coupled with a sense of urgency about improvement; they adopted challenging curricula and invested heavily in professional development. Teachers in these schools internalized responsibility for student learning; they examined their practices critically, and if they weren't working, they abandoned them and tried something else. Although these schools may be stigmatized as "low-performing" or "in need of improvement," they are working hard to learn about their practice and beginning to focus on the individual and organizational conditions that create more powerful learning for adults and children.