Science educators have suggested that, for minority and low-income students, gaps between home and school science cultures necessitate "border crossing" for successful learning in science. Our analysis used National Assessment of Educational Progress 2000 and 2005 data to assess the impact of U.S. state-level policy regarding instructional models for language acquisition for the learning of science. Specifically, we assessed whether policy favouring structured English immersion led to better student outcomes than bilingual education among Hispanic English language learners in 4th and 8th grades in the U.S. We found significantly higher science achievement among 4th grade Hispanic ELLs in states with stronger bilingual emphasis in their policy, suggesting that policy support for bilingual education could provide a better bridge to span the cultural gap between home and school science, at least for younger students.