The report explores the impact of teacher sorting, or the tendency for high-achieving students to be assigned to more effective teachers, on student achievement. It finds that teacher sorting has a significant positive effect on student achievement in both math and English language arts. The effects are particularly strong for students who start out low-achieving. The report argues that policies aimed at reducing teacher sorting, such as random assignment of students to teachers, may be counterproductive for student achievement.

The California Staff Development Policy Study was initiated to assess the possibilities and limitations of staff development in improving classroom teaching and learning. The study aims to answer four questions related to California's investment in staff development, how staff development activities are administered, and how teachers and administrators judge their effectiveness. The study yields eight main conclusions, presented in terms of investment and focusing on improving the capacities and commitments of California's educators.