The role of engineering in science and mathematics education continues to emerge as a contributing factor to improving STEM education. Efforts across different countries include the integration of engineering in K-12 curriculum, after school programs, and inservice teacher professional development. Only recently have science teacher educators begun to introduce engineering in science teacher preparation programs. By incorporating novel curriculum and design-related experiences, we can begin to explore how preservice teachers not only learn about engineering, but more importantly, learn how to teach science using engineering design. In this study, we explore different ways 45 elementary preservice science teachers characterize and construct new understandings about engineering design-based science teaching. Data were gathered via self-interviews and reflective narratives. Data analysis entailed systematic and consistent open coding across transcripts. Document analysis served as a means of triangulation, reinforcing and reaffirming claims corroborated through the analysis of interview data. Using the teacher as learner framework, we contend that preservice teachers, when engaged in an engineering design-based methods course, demonstrate positive shifts from being learners to teachers of science by embodying the participatory, performative, and experiential nature of engineering design. To support preservice teacher development, we propose that teacher education programs incorporate engineering design-based learning experiences throughout teacher preparation rather than in a single semester or year. This means integrating more and earlier opportunities for preservice teachers to develop and apply their understandings of engineering design and design teaching, potentially leading to earlier shifts and increased design-based pedagogical understandings.