Research Findings: This study illustrated whether and how ecological environments are associated with language-minority students' (N = 12,500) math and reading development from kindergarten to the eighth grade. Results identified the robust effects of preschool type, kindergarten length, classroom activities, parent-child reading, parent expectation, and teacher-child relationship on reading and math outcomes. In third and fifth grade, all significant predictors of reading outcome are at the family level: parent-child reading time and parent's expectations. Additionally, parent-child reading time also significantly predicts LMSs' reading in kindergarten. Meanwhile, predictors for math outcomes have a different pattern in the mid to late elementary periods. All predictors during this period are at the family level: parent-child reading time, parent showing love to children, and parent's expectations. Lastly, the only significant predictor for eighth grade math is teacher-child closeness. Practice or Policy: The significant findings at different grade levels suggest a multifaceted approach to policy development, including (a) supporting parent engagement, (b) high-quality preschool, and (c) multicultural teacher education and professional development.