The best way to raise achievement levels is to improve teaching; and that goal is most easily reached through a school-wide system that starts with strong, effective leadership and raises expectations for teachers and their students. Collaboration, shared goals, and the adoption of Professional Learning Communities is crucial, the author says; so is focusing on literacy, and slowing down the teaching to speed up learning. But all of this can only work if people trust one another to seek and give advice and instruction. (Contains 1 figure.)