Revisiting the Widget Effect: Teacher Evaluation Reforms and the Distribution of Teacher Effectiveness

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In 2009, TNTP’s The Widget Effect documented the failure of U.S. public education to recognize and act on differences in teacher effectiveness. We revisit these findings by compiling teacher performance ratings across 19 states that have adopted major reforms to their teacher evaluation systems. In a majority of these states, less than 3% of teachers are rated below Proficient. We also find substantial differences in the percentage of teachers rated below Proficient and Highly Effective across states. We present original survey data from an urban district illustrating that evaluators perceive more than three times as many teachers in their schools as below Proficient than they actually rate as such. Interviews with principals reveal several potential explanations for these patterns.

Last updated on 02/29/2016