Learning centers can help teachers assess students' content knowledge without penalizing them for language barriers. With the increasing number of English language learners (ELLs) in classrooms, the emphasis on mastery of content and inclusion of all students in class discussions and activities will provide all students a chance for scientific literacy. This article shows how to use learning centers to accommodate ELLs and differentiate instruction for all learners. The activities included here incorporate content teaching strategies--covering topics such as DNA, the nature of matter, and the water cycle--and assessment techniques appropriate for both ELLs and native English speakers. (Contains 2 figures and 3 online resources.)