English language development in context: The peer social networks and interactions of Spanish-speaking adolescent immigrant students

Half of immigrant students enter school in the U.S. during adolescence and face the immense challenge of education in a new country while simultaneously learning English. The need to help adolescent English learners achieve their academic potential has been hindered by the fact that to date there is little research on the second language acquisition of this age group. In particular, research is needed to better understand how second language acquisition can be affected by the unique social contexts of adolescence including peer groups and schools.;The aim of this dissertation was to better understand the role of social context in the academic English language development of adolescent immigrant students with a particular focus on peers. The frame of my dissertation draws from three literatures: an ecological model recognizing that multiple social contexts contribute to individual student outcomes in tandem with cognitive factors, interaction theories in Second Language Acquisition (SLA) emphasizing the importance of interactions to learn academic English, and social network theory which conceptualizes relationships as measurable resources.;The first study established the contribution of school contexts and language use with peers to the English proficiency of adolescent learners through secondary data analysis. Building on these findings, a mixed methods study was designed to gain insight into the processes underlying the association between language use with peers and the development of academic English among adolescents taking into account the importance of school context in shaping language learning outcomes. This study incorporates multiple data sources, including: interviews and academic English proficiency assessments with 99 Spanish-speaking adolescent immigrant students, ethnographic field notes of the 4 public New York City high schools participants attended, and in-depth case studies of 4 focal students.;In paper 2, quantitative data analysis identified patterns of linguistic peer support available to adolescent English learners across a sample of 99 Spanish-speaking youth. Findings show that academic English proficiency was positively related to having peers who spoke English with the participant half the time or more and to having peers who engaged in academic tasks with participants.;In the final paper, qualitative analysis triangulated these patterns of linguistic peer support through direct observation of language use and documented the complex interplay between school context factors and student agency in developing peers as a resource for learning academic English. Qualitative findings show that peer social networks were mediated by school policy and common teaching practices which segregated Spanish-speaking immigrant students from mainstream students and reduced English learners' opportunities to interact meaningfully around academic content.