In the United States, "A Framework for K-12 Science Education" (National Research Council, 2012) and Next Generation Science Standards (NGSS) offer a vision of rigorous science standards for all students across K-12 classrooms. As science and engineering practices (e.g., develop models, argue from evidence, construct explanations) are language intensive, engagement in these practices presents both language learning opportunities and demands to all students, especially second language learners. The purpose of this article is to describe science instructional shifts, spurred by the "Framework" and the NGSS, and language instructional shifts, informed by contemporary views in second language acquisition described in "English Learners in STEM Subjects" (National Academies of Sciences, Engineering, and Medicine, 2018). The article describes a yearlong fifth-grade science curriculum to illustrate how science and language instructional shifts are mutually supportive of each other to promote rigorous science learning and rich language use with a focus on second language learners.