This paper reports on the curriculum development stage for a larger science–literacy intervention for secondary school newcomers enrolled in an urban US school. After providing background to the study, it revises literature on efficient vocabulary instruction and reports on the Science Vocabulary Support program development, refinement, and preliminary effectiveness evaluation in a sample of 92 emergent bilinguals. Results showed that pre-to-post gains in student vocabulary retention were statistically (p < .005) and practically (d = .59) significant. These results, corroborated by weekly quizzes and interview and observational data, point out the merit of specifically targeting science-specific, technical vocabulary for instructional interventions.