Pre-service science teachers develop their teaching practices within and across the university and school contexts of their teacher education programs. The practices and visions of teaching and learning emphasized in each context are often disjointed, a problem referred to as the "two-worlds pitfall." Responding to the call for teacher education programs to better support pre-service teachers' work towards teaching that is responsive to students' thinking, this study is situated within the university and subsequent school contexts of a teacher education program. Taking an asset-based approach to pre-service teachers' learning, this study understood pre-service teachers as agentive sense makers as they appropriated teaching practices across contexts. Three pre-service science teachers participated in this qualitative case study, and the research question about how pre-service teachers appropriated teaching practices across the school and university contexts relied on the development of case narratives from analysis of interview materials, lesson planning documents, and teaching observation. These case narratives distilled central teaching practices through which pre-service teachers processes of appropriation could be understood. The findings highlight how pre-service teachers' appropriation of practices across contexts aligned with their orientation to students' thinking as problems or as resources, and that their appropriation and orientations to students' thinking were consistent across the contexts of the two-worlds pitfall. Pre-service teachers' experiences with tensions in their school contexts highlighted their agency to maintain, re-envision, and reject the visions of teaching that did or did not align with their patterns of appropriation and orientations to students' thinking that were consistent across contexts. As such, this study challenges traditional models of the two-worlds pitfall that anticipate significant shifts in pre-service teachers' practices across contexts. Rather, this study highlights the availability of productive ideas about responsive and rigorous instruction in pre-service teachers' thinking, and missed opportunities for teacher educators to draw out and leverage those ideas to support pre-service teachers' development of teaching that capitalizes on students' thinking. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]