We study the returns to experience in teaching, estimated using supervisor ratings from classroom observations. We describe the assumptions required to interpret changes in observation ratings over time as the causal effect of experience on performance. We compare two difference-in-differences strategies: the two-way fixed effects estimator common…

An evaluation system that is designed to support and improve teacher practice--rather than simply to assess and manage teacher performance--would have as its foundation effective and reliable processes to observe classroom practice and give teachers useful feedback. Such an improvement-focused evaluation system should be aligned with and…