The aim of the present study is to explore a variety of cognitive and social variables which are most relevant to children's linguistic success in an educational setting. The study examines kindergarten English language outcomes in classrooms containing monolingual English speaking children and bilingual children who speak English and one other language. Data from the National Center for Early Development and Learning Multistate Study of Pre-Kindergarten (2001-2003) regarding classroom and student characteristics were used for bilingual (N = 120) and monolingual (N = 534) children. Hierarchical regression analysis (Study 1) and path analysis (Study 2) were conducted to determine the cognitive and social variables present in preschool that are most predictive of English skills in kindergarten. The results of the studies demonstrate that social variables were important for both monolingual and bilingual children. Personality variables were more predictive for monolingual children, whereas teacher relationship variables were more important for bilingual children. Simple and routine adult interaction was predictive of English skills in both groups, which may indicate the importance of implicit learning over explicit instruction in early language acquisition. The present studies found different predictors of English language skills for monolingual and bilingual kindergarteners.