The purpose of this paper is to report themes identified in questions K-12 mainstream teachers in one U.S. school district posed about differentiating instruction for English language learners (ELLs) in order to hear directly from teachers about topics they would like to learn more about. Teachers in the district completed a selected-response and open-ended survey to inform future professional development opportunities. Findings suggest that most teachers work with ELLs but are underprepared to teach them. Teachers posed questions about curriculum and assessment; instruction; building community; language difference versus disability; and where to start in teaching ELLs. Conclusions are drawn about how well ELLs are being educated in the district. Implications for teacher professional development and policy are also discussed.