This paper examines the causal impact of a large-scale Turkish language training program on the academic performance, school participation, and mental well-being of Syrian refugee children in T¨urkiye. Using rich administrative data and a staggered difference-in-differences design, we find that the program led to improvements in Turkish language and Math scores of refugee students, along with a significant reduction in their school absences. The language gains and associated improvements in school outcomes are more pronounced for younger refugee children with lower pre-program academic performance, which suggests that early language interventions are more effective for integration. In addition, we provide evidence that the language training program generated modest positive spillovers on native students. Finally, we identify mental health as a potential key channel through which the program enhanced educational outcomes, as alleviating language barriers improved concentration, reduced anxiety, and decreased bullying. Our findings underline the critical role of language training in improving refugee students' educational outcomes and mental well-being, and fostering social cohesion.