This study explores the experiences of Mexican-origin children and adolescents returning to Mexico from the U.S., focusing on their linguistic, cultural, and educational adaptation. These returnees, often English-dominant and bicultural, face significant challenges in reintegrating into Mexican schools and communities, where they encounter linguistic barriers, social exclusion, and rigid educational systems. Through the lens of the Plurilingual Multiliteracy Spanish Course (PMSC), an innovative Spanish as a Second Language program, this research examines how plurilingual pedagogies of multiliteracies can foster agency and social cohesion among returnee students. The study employs a critical case study design, analyzing the experiences of three participants at different stages of return migration. Findings reveal that returnee students leverage their linguistic and cultural capital to navigate educational and social challenges, using strategies such as code-switching, peer collaboration, and cultural representation to assert their plurilingual identities and build supportive networks. The PMSC, grounded in plurilingualism and multiliteracies, empowers students to bridge linguistic and cultural divides, enhancing their academic success and social integration. This research underscores the transformative potential of language education in promoting equity, inclusion, and agency among transnational students, offering valuable insights for addressing the needs of returnee populations in Mexico’s educational system, particularly in the context of increasing deportations under U.S. immigration policies.