Science vocabulary can be abstract (e.g., "photosynthesis," "ecosystem") and have different meanings than in daily life (e.g., "class," "work," "power"). For this reason, understanding individual vocabulary words isn't enough for learners to be successful. The meaning is embedded in basic syntax, language functions, and patterns of discourse. The language aspect of science complicates matters even more for English language learners (ELLs) not yet proficient in English. Studies report that "content-based" approaches to teaching ELLs improve content understanding and develop language proficiency (Chamot and O'Malley 1994; Echevarria, Vogt, and Short 2002; Lee and Fradd 1998; Nutta, Bautista, and Butler 2010). In other words, if educators make science content comprehensible and provide opportunities for ELLs to demonstrate their content understanding, their language skills will grow. As English communication skills grow, understanding of science concepts increases. This article presents an approach to supporting ELLs' language growth in a constructivist-oriented science classroom. We compare and contrast a framework for inquiry-based science instruction called the "5E Learning Cycle" (Bybee 1997) and a framework for language instruction called the "Sheltered Instruction Observation Protocol" (SIOP; Echevarria, Vogt, and Short 2002). Then, the authors provide a lesson using both frameworks.