This article assesses the effects of Tulsa, Oklahoma’s early childhood education programs on social-emotional outcomes, examining teacher ratings of children’s behavior from the Adjustment Scales for Preschool Intervention and a measure of attentiveness using fixed effects regressions with propensity score matching. The sample includes 2,832 kindergarten students in 2006, of whom 1,318 participated in the Tulsa Public Schools (TPS) pre-K program and 363 participated in the CAP of Tulsa County Head Start program the previous year. Program participation was associated with lower timidity and higher attentiveness for TPS pre-K alumni and a marginally significant reduction in timidity for Head Start alumni. Results were similar for the free lunch-eligible subsample. We conclude that high-quality, school-based preschool programs can enhance social-emotional development.