In this randomized field trial of KindergARTen Camp, a 6-week summer enrichment program in literacy and the fine arts, we analyzed the summer learning outcomes of 93 treatment and 35 control students from high-poverty schools in Baltimore, Maryland. This experiment offers evidence concerning the causal effect of the program on 5 measures of students' literacy achievement. We found treatment effects during the summer months that were of both practical and statistical significance on the Developmental Reading Assessment (DRA) and the Word List A assessments. In addition, results from surveys of KindergARTen Camp students, parents, and teachers revealed strong satisfaction with the program. We conclude by discussing the contextual factors that may have contributed to these results. (Contains 9 tables and 2 footnotes.)