Has the achievement of U.S. students improved over the past half century? Have gaps between racial, ethnic, and socioeconomic groups widened or narrowed? These and similar questions provoke near-constant conversation. But answers are uncertain, partly because research to date has yielded inconsistent findings. In this article, the authors bring…

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…

The Progress in International Reading Literacy Study (PIRLS) is an international assessment of student performance in reading literacy at the fourth grade. PIRLS measures students in the fourth year of formal schooling because this is typically when students' learning transitions from a focus on "learning to read" to a focus on…