This project aims to understand how evaluation can be better used as a tool for teacher development, offering districts cost-effective routes to improving teacher quality and student achievement. The research team will work with the Tennessee Department of Education to implement an intervention in which low-performing teachers are paired with an expert teacher in their school. If effective, the project will have implemented and demonstrated a program that 1) helps school principals provide support to struggling teachers, 2) supports teacher collaboration, 3) builds teacher leadership opportunities, and 4) improves teacher effectiveness.