State-specific licensing policies and pension plans create mobility costs for educators who cross state lines. We empirically test whether these costs affect production in schools--a hypothesis that follows directly from economic theory on labor frictions--using geo-coded data from the lower-48 states. We find that achievement is lower in…

This study examined whether being taught by a teacher with a high "value-added" improves a student's long-term outcomes. The study analyzed more than 20 years of data for nearly one million fourth- through eighth-grade students in a large urban school district. The study reported that having a teacher with a higher level of value-added…