Reconciling Different Estimates of Teacher Quality Gaps Based on Value Added

This policy brief reviews evidence about the extent to which disadvantaged students are taught by teachers with lower value-added estimates of performance, and seeks to reconcile differences in findings from different studies. We demonstrate that much of the inequity in teacher value added in Washington state is due to differences across different districts, so studies that only investigate inequities within districts likely understate the overall inequity in the distribution of teacher effectiveness because they miss one of the primary sources of this inequity.