Principals (policy makers) have debated the progress in U.S. student performance for a half century or more. Informing these conversations, survey agents have administered seven million psychometrically linked tests in math and reading in 160 waves to national probability samples of selected cohorts born between 1954 and 2007. This study is the first to assess consistency of results by agency. We find results vary by agent, but consistent with Flynn effects, gains are larger in math than reading, except for the most recent period. Non-whites progress at a faster pace. Socio-economically disadvantaged white, black, and Hispanic students make greater progress when tested in elementary school, but that advantage attenuates and reverses itself as students age. We discuss potential moderators.