Teacher value-added models (VAMs) must isolate teachers' contributions to student achievement to be valid. Well-known VAMs use different specifications, however, leaving policymakers with little clear guidance for constructing a valid model. We examine the sensitivity of teacher value-added estimates under different models based on whether they…

Like many states throughout the nation, Pennsylvania is in the midst of major reforms to its teacher evaluation system. Under the new system, the state will base annual evaluations on several measures, including supervisor observations using the Framework for Teaching (FFT) and, for many teachers, their contributions to student achievement growth…