Interventions designed to develop teacher leadership are common, but whether they also improve student achievement is less clear, and the case of one program offers useful insight. The Mountaineer Mathematics Master Teacher (M3T) project, a 5-year networked improvement community across West Virginia, set out to grow a corps of Math Teacher Leaders who could strengthen mathematics instruction while building the state’s capacity to leverage local leaders in statewide initiatives.

Serving as the project’s evaluator, WestEd analyzed West Virginia Department of Education data to examine whether participation in M3T was associated with student mathematics achievement in grades 6 through 8. The findings are promising: When prior scores and demographics are controlled for, students’ exposure to participating teachers was associated with higher achievement, and students who received 2 years of instruction from Math Teacher Leaders showed statistically significantly higher outcomes. The report offers state policymakers, district leaders, and researchers early evidence that investing in teacher leadership may yield measurable gains for students.