The EdResearch for Action Overview Series provides evidence-based insights for K-12 education decision makers on effectively supporting multilingual students classified as English Learners (ML-ELs). It emphasizes the need for differentiated language development services tailored to ML-ELs' diverse needs, the importance of integrating cultural responsiveness into pedagogy, and the efficacy of bilingual and dual language programs in promoting academic achievement and linguistic equity. Challenges highlighted include inadequate teacher preparation, funding disparities, and the risks of implementing one-size-fits-all approaches and grade retention policies.