Association for Public Policy Analysis & Management

Background: Teacher quality is among the most variable school-based influences on student learning. However, as with other schooling resources, not all students have equitable access to high-quality teachers, whether measured by observable credentials or effects on student achievement. In response to these discrepancies, policymakers have become increasingly interested in using financial incentives to increase the number of effective teachers in high poverty and other hard-to-staff schools. There is relatively little evidence, however, on whether additional compensation for teachers in low income schools improves either teacher hiring or students’ academic outcomes.

Purpose: In this study, we assess an incentive policy in Washington State designed to increase the supply of effective teachers in high poverty schools. The Challenging Schools Bonus (CSB) awarded a $5,000 annual bonus to teachers who earned certification through the National Board for Professional Teaching Standards (NBPTS) and worked in schools with a high proportion of students qualifying for subsidized lunches. The CSB provides a good test of the potential for targeted incentives based on teaching credentials as it is one of the few credentials consistently linked to student achievement gains in the teacher effectiveness literature. As with other indicators of teacher quality, NBCTs are less likely to teach in high poverty schools. At least five other states offer additional compensation for National Board certified teachers (NBCTs) that is similar to the CSB and two states have included National Board certification status in their teacher equity reports.

Findings: We study the effects of the NBCT bonus policy in Washington using a regression discontinuity design based on the schoolwide eligibility rule. We find that eligibility for the additional compensation increased the number of NBCTs in high poverty schools by improving hiring, encouraging certification among incumbent teachers, and reducing turnover among Board certified teachers. Over the first six years of the program, we estimate that eligibility increased the proportion of NBCTs by about 0.7–1.6 percentage points per year. Despite the evident improvements in teacher staffing, we do not find positive student achievement effects from the bonus policy. Based on estimates of the relative effectiveness of NBCTs at raising student achievement found in the literature, our estimated effects on school staffing imply annual improvements in student learning of less than 0.001 standard deviations per year of eligibility. Consistent with this prediction, our direct estimates of the effects of the bonus policy on student achievement are near zero and not statistically significant.

Significance: The study documents the importance of several theoretical issues related to strategic compensation policies that target teacher credentials. Although we find that the policy increased hiring of NCBTs and reduced their attrition, the largest effects on teacher certification status operate through increases in the number of incumbent teachers earning professional certification. The achievement effects of such targeted bonuses may be less than that suggested by their effects on observable characteristics.