To provide new and needed knowledge about what student and school characteristics are associated with EL success in pre-k and the early grades, this study examines attendance, grades, test scores, and English proficiency from two groups of Chicago Public Schools (CPS) ELs (14,058 students in pre-k and 16,651 students in the early grades K-3) to answer the following research questions: -What are the factors associated with stronger outcomes for ELs in pre-k and the early grades? -To what extent can schools identify ELs who would benefit from additional support? (author abstract)