D.C.’s high-stakes teacher evaluations raise teacher quality, student achievement
90% of the turnover of low-performing teachers occurs in high-poverty schools
July 27, 2017—Though the Every Student Succeeds Act excludes any requirements for states about teacher evaluation policies, the results from a once-controversial high-stakes system in Washington, D.C., make a strong case that states should persevere with reform. IMPACT was launched in 2009-10 by then-chancellor Michelle Rhee and continued under her successor, Kaya Henderson, when Rhee stepped down amidst Mayor Adrian Fenty’s losing reelection bid. In a new research article for Education Next, Thomas Dee of Stanford University and James Wyckoff of the University of Virginia report how IMPACT, the District of Columbia Public Schools’ (DCPS) eight-year effort to link teacher retention and pay to performance, is promoting higher rates of turnover among the lowest-performing teachers, especially in high-poverty schools, with positive impacts on student achievement.
Dee and Wyckoff find that teacher turnover under IMPACT has increased student achievement in both math and reading across DCPS. Overall, the exit of low-performing teachers is estimated to improve student achievement by 0.21 of a standard deviation in math—between one-third and two-thirds of a year of learning, depending on grade level. In reading, student achievement is estimate to increase by 0.14 of a standard deviation. At DCPS, more than 90 percent of the turnover of low-performing teachers occurs in high-poverty schools, where the proportion of exiting teachers who are low performers is twice as high as in low-poverty schools.
Under IMPACT, all DCPS teachers receive a single score ranging from 100 to 400 points at the end of each school year. Scores are based on multiple classroom observations, measures of student learning, and commitment to the school community. Relative to typical teacher-evaluation systems, IMPACT creates substantial differentiation in ratings and uses concrete incentives for teachers to improve their ratings. Teachers identified as “minimally effective” have one year to improve their rating and avoid dismissal. On the other side of the spectrum, teachers rated “highly effective” are eligible for a bonus of up to $25,000, and repeated high ratings trigger a permanent salary boost.
In 2009‒10 and 2010‒11, 69 percent of teachers were rated “effective,” 14 percent were rated “highly effective,” 2 percent were judged “ineffective,” and another 14 percent were deemed “minimally effective.” Ninety-five percent of teachers identified as ineffective were dismissed. Among those identified as minimally effective, 14 percent were dismissed and 27 percent voluntarily left DCPS. Minimally effective teachers who chose to stay at DCPS improved their performance by roughly 11-points on the IMPACT scale, suggesting that threat of dismissal lead to successful instructional improvement efforts.
“Our results indicate that, under a robust system of performance evaluation, the turnover of teachers can generate meaningful gains in student outcomes, particularly for the most disadvantaged students. The eight-year history of IMPACT shows that such efforts are not politically impossible,” the authors conclude.
To receive an embargoed copy of “A Lasting Impact: High-stakes teacher evaluations drive student success in Washington, D.C.” or to speak with the authors, please contact Jackie Kerstetter at firstname.lastname@example.org. The article will be available Tuesday, August 1 on www.educationnext.org and will appear in the Fall 2017 issue of Education Next, available in print on August 30, 2017.
About the Author: Thomas Dee is a professor of education and director of the Center for Education Policy Analysis at Stanford University, and a research associate at the National Bureau of Economic Research. James Wyckoff is the Curry Memorial Professor of Education and Policy and director of EdPolicyWorks at the University of Virginia.
About Education Next: Education Next is a scholarly journal committed to careful examination of evidence relating to school reform, published by the Hoover Institution at Stanford University and the Harvard Program on Education Policy and Governance at the Harvard Kennedy School. For more information, please visit www.educationnext.org.