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…

States across the country are developing systems for evaluating school principals on the basis of student achievement growth. A common approach is to hold principals accountable for the value added of their schools--that is, schools' contributions to student achievement growth. In theory, school value added can reflect not only principals'…