The Impact of Measuring and Publicizing Teacher Value-Added on Teacher Turnover and School Performance: The Case of Ohio's 2011 Value-Added Pilot Program

Abstract

Research has shown that teacher quality--as measured by the annual test score gains of their students--is an important predictor of students' educational and life outcomes. As a result, teacher evaluation systems increasingly employ student test score gains, otherwise known as teacher "value added" scores. Unfortunately, there has not been much research into whether a school and district's use of these evaluation systems actually leads to an improvement in student achievement. This study examines a unique pilot program in Ohio that brought value-added measurement methods to a sample of districts in 2011, which enables a comparison of outcomes between districts that did and did not utilize value-added metrics. Additionally, because individual teacher value-added scores were published in a prominent newspaper shortly thereafter, this case allows for the estimation of the impact of publishing teacher evaluations on teacher turnover and the performance of school districts. The results indicate that schools that participated in the study and had teachers' scores published experienced greater teacher turnover and higher student achievement gains than schools that did not. Specifically, immediately after the pilot began in 2011, the average student in a participating school experienced the equivalent of almost 9 additional "days of learning" per year as compared to the average student in a school that did not participate. Then, in 2014--immediately after the public dissemination of test scores--student achievement increased by a similar 8 additional days' worth of learning. The analysis also reveals that low-rated teachers left at higher rates than high-rated teachers during these years, which is consistent with the notion that improvements in teacher quality are responsible for students' achievement gains.