This article reviews findings from scientific research that has been conducted in the United States since 1980 on the educational outcomes of English language learners (ELLs). The studies selected for review here are a subset of a more comprehensive body of research conducted during this period that is reported in Genesee, Lindholm-Leary, Saunders, and Christian (in press). Major findings on the oral language, literacy, and academic achievement of ELLs are discussed in 3 separate sections of this article, in addition to a discussion of the gaps and shortcomings in current research in each domain. Recommendations for future research are also presented, including the need for sustained theory-driven research that examines the longitudinal development of and influences of instruction on the oral language, literacy, and academic skills of diverse groups of ELLs across the K-12 span.