Mentoring has become an extremely popular policy for improving the retention and performance of new teachers, but we know little about its effects on teacher and student outcomes. I study the impact of mentoring in New York City, which adopted a nationally recognized mentoring program in 2004. I...

The challenge of designing effective performance measurement and incentives is a general one in economic settings where behavior and outcomes are not easily observable. These issues are particularly prominent in education where, over the last two decades, test-based accountability systems for...