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The Effect of Rigorous Teacher Evaluations on Workforce Quality Part 2 : Teacher Exits and Student Achievement

This brief is a follow-up to our previous brief on how the Effective Teachers Initiative (ETI) has changed the composition of teacher exits from HISD. The companion brief shows that the ETI has increased the exit rate of ineffective teachers relative to other teachers. This brief documents how much the compositional effect on exiting teachers improves student achievement. While we estimate a positive effect on achievement operating through the change in the composition of exiting teachers, it is very small. The reason is that even though the ETI has created a noticeable divergence in exit rates between lowand high-performing teachers, there are still many effective teachers who exit. Put differently, although teacher exit and retention are better aligned with student achievement goals under the ETI, they are not well enough aligned for the compositional change to induce meaningful achievement gains.