This paper highlights challenges and opportunities as English Language Learners engage with the Next Generation Science Standards. These new standards represent a major shift in science instruction, toward an explicit focus on scientific sense-making, language use, and scientific practices. These practices also place significance on developing explanations and argumentation from evidence as well as on language learning opportunities. The authors discuss in detail how four core science and engineering practices provide opportunities for ELLs: Developing and using models. Developing explanations (for science) and designing solutions (for engineering). Engaging in argument from evidence. Obtaining, evaluating, and communicating information.