The Future of Education

Student achievement is well understood to be a constellation of various factors, including family background, student characteristics, and school factors (Ker, 2016; Reynolds, Sammons, De Fraine, Townsend, & Van Damme, 2011). While family background and individual student characteristics are important for understanding student achievement, they offer little direction for policymakers and educators regarding how to improve student achievement. By contrast, most of school factors are malleable and thus have important policy implications for improving student achievement. Among the wide array of school factors affecting student achievement, school leadership has drawn much scholarly attention in educational literature because it is found to be the second most important variable that affects student learning, following classroom instruction (Leithwood, Louis, Anderson, & Wahlstrom, 2004). However, it is unclear the way in which school leadership affects student achievement. Accordingly, identifying mechanisms and processes through which school leadership affects student achievement is still important especially in light of indirect effects of school leadership on student achievement that most of prior research found (e.g., Hallinger & Heck, 1996; Louis, Dretzke, & Wahlstrom, 2010). Using a nationally representative U.S. sample of ninth graders from the High School Longitudinal Study of 2009-2012, we pay attention to the role of affective principal-teacher and teacher-student relationships in explaining the effect of school leadership on student achievement. Specifically, the current study examines the role of collective teacher expectations—defined as teacher expectations for student success at the school level, rather than at the individual level—in linking principal support to student achievement. We used multilevel structural equation modeling techniques to test a conceptual model that identifies collective teacher expectations as a key mediator by which principal support shapes students' math achievement. Results showed that principal support played an important role in students' math achievement, particularly their achievement change through teacher expectations at the school level. Findings suggest that collective teacher expectations are potential mechanisms through which principal support affect student achievement.

Keywords: principal support, collective teacher expectations, math achievement, multilevel structural equation modeling;