High teacher turnover imposes numerous burdens on the schools and districts from which teachers depart. Some of these burdens are explicit and take the form of recruiting, hiring, and training costs. Others are more hidden and take the form of changes to the composition and quality of the teaching staff. This study focuses on the latter. We ask…

Efforts to improve teachers' knowledge and to change the nature of curriculum materials have dominated mathematics reforms since the late 1990s. In this article, we compared middle school teachers' mathematical knowledge for teaching (MKT) and curriculum use between 2005 and 2016 to assess progress toward these key goals. We found teachers' MKT…

Socioeconomic achievement gaps have long been a central focus of educational research. However, not much is known about how (and why) between-district gaps vary among states, even though states are a primary organizational level in the decentralized education system in the United States. Using data from the Stanford Education Data Archive (SEDA),…