Null Effects of an Intensive Teacher Leadership and Coaching Program at Scale

Teacher coaching programs have shown promising effects on student achievement, but these effects vary substantially across programs and seem susceptible to scaling problems. Additionally, the effect of coaching on teacher retention is not known. In this paper, we evaluate a program in which current teachers are released from the classroom part-time to coach and evaluate other teachers. This program was rolled out in five cohorts of schools and eventually reached over 6,000 mentee teachers, presenting a unique opportunity to study the effect of large-scale coaching on teachers and students. We use a difference-in-differences approach with modified estimators to account for the staggered roll-out and find no effects on teacher retention or student test scores.