Problems with the use of test scores to evaluate teachers

In new EPI report, leading educational testing experts caution against heavy reliance on the use of test scores in teacher evaluation

Student test scores are not reliable indicators of teacher effectiveness, even with the addition of value-added modeling (VAM), a new Economic Policy Institute report by leading testing experts finds. Though VAM methods have allowed for more sophisticated comparisons of teachers than were possible in the past, they are still inaccurate, so test scores should not dominate the information used by school officials in making high-stakes decisions about the evaluation, discipline and compensation of teachers.

The Obama administration has encouraged states to adopt laws that use student test scores as a significant component in evaluating teachers, and a number of states have done so already. The Los Angeles Times recently used value-added methods to evaluate teachers in the Los Angeles Unified School District based on the test scores of their students, and Secretary of Education Arne Duncan supported the paper's decision to publicly release this information, asserting that parents have a right to know how effective their teachers are.  But the conclusions of the expert co-authors of this report suggest that neither parents nor anyone else should believe that the Los Angeles Times analysis actually identifies which teachers are effective or ineffective in teaching children because the methods are incapable of doing so fairly and accurately.

The distinguished authors of EPI's report, Problems with the Use of Student Test Scores to Evaluate Teachers, include four former presidents of the American Educational Research Association; two  former presidents of the National Council on Measurement in Education;  the current and two  former chairs of the Board of Testing and Assessment of the National Research Council of the National Academy of Sciences;  the president-elect of the Association for Public Policy Analysis and Management;  the former director of the Educational Testing Service's Policy Information Center and a former associate director of the National Assessment of Educational Progress; a former assistant U.S. Secretary of Education; a former  and current member of the National Assessment Governing Board; and the current vice-president, a former president, and three other members of the National Academy of Education.

The co-authors make clear that the accuracy and reliability of analyses of student test scores, even in their most sophisticated form, is highly problematic for high stakes decisions regarding teachers . Consequently, policymakers and all stakeholders in education should rethink this new emphasis on the centrality of test scores for holding teachers accountable.