Research suggests that the influence of principal leadership on achievement is not direct, but instead, works indirectly, through an array of mediating factors. Despite this knowledge, substantial gaps in our understanding remain: Empirical evidence on the effects of leadership on achievement is largely limited to studies of principal leadership. Prior research does not clearly identify which factors and combinations of factors mediate between school leadership and student achievement.
This study is designed to address four broad research questions: (a) To what degree is student achievement influenced by schools and principals, i.e., school and principal value added? (b) What are the effects of specific leadership practices on school and principal value added? (c) How do teacher hiring and retention and other factors mediate how leadership influences student achievement? (d) How do the effects of leadership and the role of mediating factors vary across school contexts?
Our research includes two components. The first involves a series of surveys conducted in 300 Florida schools that have recently changed principals. This component investigates the impact of a range of school leadership practices on student achievement, with particular attention paid to the consequences of principals’ teacher hiring practices.
The second component uses statewide data to investigate how principals influence teacher hiring and retention. By using these data to link individual teachers and principals to their schools, students, and student achievement, we are able to calculate teacher value-added estimates: Estimates of teachers' unique contributions to overall school achievement for teachers in nearly all elementary and secondary schools in the state. With these estimates, we can study whether certain principals are more likely to hire and retain high value-added teachers.
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