This project examines language and academic outcomes in K-4 students who have different educational experiences in bilingual education programs. Schools serving students from linguistically diverse backgrounds follow different types of bilingual educational programs. Additionally, teachers develop different classroom strategies to meet their students' needs. This project examines teacher pedagogical practices that predict student language and academic content learning. The project advances understanding of child language development across three interacting levels of context: type of educational program, teacher classroom practices, and child factors. The outcomes of this research can provide evidence-based guidance to bilingual education programs and direct teachers’ language practices to meet the needs of students from diverse language backgrounds. This project provides research training in developmental science to graduate and undergraduate students across the departments of Psychology, Education, and Human Development and Family Studies.<br/><br/>This project examines whether flexible language use by teachers in bilingual education classrooms (such as translation and making cross-linguistic connections) is associated with better student outcomes than language separation, a common approach in bilingual education. This project uses a longitudinal approach to examine language and academic performance of students attending racially, ethnically, and linguistically diverse schools. The teachers of participating students are observed teaching lessons in math and literacy in the fall and spring of each academic year. Teachers also participate in annual semi-structured interviews. Researchers gather data about classroom teacher practices across different types of bilingual education programs to predict student language and academic progress in grades K-4 using multivariate growth modeling techniques. The outcomes of this project can advance cognitive theories of bilingualism and language learning and inform educational practice.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.