Unstructured activity periods are central components of early childhood education programs. Deficits in social communication and social interaction presented by children with autism spectrum disorder (ASD) become apparent in these settings during unstructured activities, such as outdoor recess. Thirty-two preschool-age children with and without ASD participated in the "Buddy Game," a structured, cooperative play curriculum that focused on natural peer-peer modeling and imitation. The "Buddy Game" used familiar songs to promote peer proximity and discrete social bids between peers during outside time. A multiple baseline design across three classrooms was used to study curriculum effects on discrete social bids of children with ASD. Results demonstrated increased social bids from children with ASD to their peers with neurotypical development (NTD) across classrooms. In one classroom, effects maintained after intervention stopped and generalized to other times of the day. Implications for integrated educational settings and early childhood curricula are discussed.