There are three primary measures of teaching performance: student test-based measures (i.e., value added), classroom observations, and student surveys. Although all three types of measures could be biased by unmeasured traits of the students in teachers' classrooms, prior research has largely...

Educational interventions are often evaluated and compared on the basis of their impacts on test scores. Decades of research have produced two empirical regularities: interventions in later grades tend to have smaller effects than the same interventions in earlier grades, and the test score...

In the three decades before the pandemic, mean achievement of U.S. 8th graders in math rose by more than half a standard deviation on the National Assessment of Educational Progress (NAEP). Between 2019 and 2022, U.S. students had forfeited 40 percent of that rise. To anticipate the consequences...