This multiple case study examined the reflections of elementary teachers as they taught science to English language learners (ELLs). The six participants in this study developed explanations about their science teaching with ELLs as they engaged in reflective practice using video-based tools during a professional development experience. Open coding was used to analyze the data and cross-case comparison identified similarities and differences among the participants' cases. Participants' reflections indicated that knowledge of their students' culture and backgrounds influenced their teaching practices and the focus of their reflections. Themes that emerged from participants' reflections related to navigating the school world, managing the technical classroom, negotiating barriers, nurturing all students, and understanding learning. Findings illustrate the importance of examining teachers' reflective writings in order to develop an understanding of how they use students' backgrounds to inform their teaching practice and how they develop their science teaching practice with ELLs.