The current study provides new evidence on the sustained benefits of preschool attendance on a broader range of skills--both academic and executive functioning (EF)--than many prior studies have examined. Using propensity score methods, we predicted children's (N = 920, M age at 1st = 6.5 years) literacy, language, math, and EF skills in kindergarten and again at first-grade (2020-2021) based on whether they had attended public preschool (school-based pre-k; Head Start) versus no preschool. In our race-ethnically diverse sample of children (48% Hispanic/Latinx; 21% Black; 14% White; 9% Native American; 9% multiracial) from low-income families, preschool attenders showed advantages on English literacy, English language, and math in kindergarten, which mostly persisted into first-grade. Preschool did not boost EF in kindergarten or first-grade. [This article was written with the Tulsa SEED Study Team.]