Teacher evaluation: Are principals' classroom observations accurate at the conclusion of training?

Teacher evaluation commonly includes classroom observations conducted by principals. Despite widespread use, little is known about the quality of principal ratings. We investigated 1,324 principals' rating accuracy of six teaching practices at the conclusion of training within an authentic teacher evaluation system. Data are from a video-based exam of four 10-minute classroom observations. Many-Facet Rasch modeling revealed that (1) overall principals had high accuracy, but individuals varied substantially, and (2) some teaching episodes and practices were easier to rate accurately. For example, promotes critical thinking was rated more accurately than uses formative assessment. Because Many-Facet Rasch modeling estimates individuals' accuracy patterns across teaching episodes and practices, it is a useful tool for identifying areas that individual principals, or groups, may need additional training (e.g., evaluating formative assessment). Implications for improving training of principals to conduct classroom observations for teacher evaluation are discussed.