Research Findings: The purpose of this study was to examine whether approaches to learning significantly mediated relations between cognitive flexibility (a component of executive functions) and school readiness in Head Start preschoolers. A total of 191 children from 22 Head Start classrooms were directly assessed on cognitive flexibility and school readiness. In addition, teachers rated children's approaches to learning in 3 domains (competence motivation, attention/persistence, and attitude toward learning) using the Preschool Learning Behaviors Scale (P. A. McDermott, L. F. Green, J. M. Francis, & D. H. Stott, 2000). Results of multilevel mediation analyses revealed that 1 component of approaches to learning--attention/persistence--significantly mediated the relation between cognitive flexibility and school readiness. These results suggest that part of the effect of cognitive flexibility on school readiness may be related to cognitive flexibility supporting children's approaches to learning. Practice or Policy: This information may be useful to researchers and practitioners attempting to improve school readiness by improving children's cognitive flexibility. The findings suggest, at a very preliminary level, that improvements to children's cognitive flexibility may lead to improved approaches to learning as well as academic school readiness. This information is important to consider as preschool programs increasingly target children's executive functions. (Contains 5 tables.)