New systems that seek to evaluate teachers with regard to their classroom quality often rely on observation instruments that capture general instructional pedagogies. However, decades of research suggest that content-specific dimensions of instruction also are important to differentiate teachers and improve student outcomes. We explore the degree…

Education agencies are evaluating teachers using student achievement data. However, very little is known about the comparability of test-based or "value-added" metrics across districts and the extent to which they capture variability in classroom practices. Drawing on data from four urban districts, we found that teachers were…