Principals key to identifying teachers who produce largest achievement gains

Monday, February 27, 2006

Principals are very good at identifying those teachers who produce the largest achievement gains in their schools, and also those who produce the smallest, according to a new study released by Education Next: A Journal of Opinion and Research.

Harvard University's Brian Jacob and Brigham Young University's Lars Lefgren found that principals do a good job of assessing overall teacher effectiveness and are especially adept at identifying those teachers who are in the top or bottom groups, based on how much students are learning in their classes.

As interest in linking teachers' salaries directly to student achievement grows in states across the nation, Jacob and Lefgren see an important role for principals to play in determining merit pay. The evidence in their research suggests that merit-pay programs that focus on the highest- and lowest-performing teachers should be based in part on evaluations by principals.

Jacob and Lefgren surveyed all 13 elementary school principals in a midsized school district in the western United States. The principals assessed 202 teachers in grades two through six. They were asked to provide a rating of overall teacher effectiveness and to judge ten specific teacher characteristics, including dedication and work ethic, classroom management, parent satisfaction, and ability to improve math and reading achievement.

The researchers looked at the principals' overall ratings of teachers and examined how different qualities in the teachers were valued. They compared a principal's assessment of a teacher's effectiveness at raising student achievement in reading or math with the actual ability of that teacher to do so as measured by his or her value-added.

In addition to helping identify the best and the worst teachers, Jacob and Lefgren found that principals' ratings of teachers -- both overall ratings and ratings of teachers' ability to improve achievement -- were effective predictors of future achievement gains by their students.

To find out more about Jacob's and Lefgren's research read "When Principals Rate Teachers" in the new issue of Education Next, now online at

Brian Jacob is assistant professor of public policy at the John F. Kennedy School of Government at Harvard University and a faculty research fellow with the National Bureau of Economic Research. Lars Lefgren is assistant professor of economics at Brigham Young University.

Education Next is a scholarly journal published by the Hoover Institution that is committed to looking at hard facts about school reform. Other sponsoring institutions are the Harvard Program on Education Policy and Governance, the Thomas B. Fordham Foundation, and the Manhattan Institute for Policy Research.

—New research in Education Next notes principals may be vital in determining merit pay—