Stewart, Mary Amanda, 1979-2020-08-212020-08-212020-088/3/202020-Aughttps://hdl.handle.net/11274/12459The influx of immigrants has contributed significantly to the exponential diversification of culture and language represented in classrooms from preschool to high school (Ataiants et al., 2018). To ensure the academic success of culturally and linguistically diverse students, it is essential to meet their unique curricular needs within these multicultural contexts. A crucial component of academic success in the United States is the acquisition of English. Yet the ways schools have narrowly attempted to address this need, through English-only practices that are void of encompassing students’ full linguistic repertoires and cultural ways of knowing, continue to marginalize emergent bilinguals, particularly adolescent newcomers (Menken, 2013). This population faces more challenges compared to their younger counterparts because of their late entrance into U.S. schools, critical age in life, high academic demands, and limited time to acquire necessary credits for graduation (Fu & Graff, 2009). This qualitative case study illustrates the ways cultural and linguistic semiotic mediators support adolescent newcomer’ literacy development in school guided by a proposed conceptual framework, Critical Semiotic Mediation. The study took place in a North Texas high school where selection of participants came from courses designated for newcomers. Open and analytical coding was used to analyze data, discuss findings and significance (Dyson & Genishi, 2005). Two major findings in the ways that semiotic mediation supported students’ literacy development in school were the concepts of Semiotic Mediation Spaces and Agency Mobilizers. A model illustrated the symbiotic and interactive relationship of Agency Mobilizers within Semiotic Mediation Spaces. In discussing the Semiotic Mediation Spaces, the spaces that the students had contact with including Home, School, and Affinity spaces were identified. Then the Agency Mobilizers represented by gears that function within the spaces were discussed. Three gears; Future Self, School Literacies, and Social Identity were identified. This study contributes to the literature of Identity Theories, Culturally Sustaining Pedagogy and the diversity of adolescent newcomers. The findings imply the need for a Culturally Sustaining approach to pedagogy, policy and research.application/pdfenCritical literacySemiotic mediationEmergent bilingualMultilingualSdolescent newcomerSecondaryEnglish learnerThesis2020-08-21