In an effort to document teachers' enactments of new reform in science teaching, valid and scalable measures of science teaching using engineering design are needed. This study describes the development and testing of an approach for documenting and characterizing elementary science teachers' multiday enactments of engineering design-based science teaching. Using the tenets of ambitious teaching, we explore how Grade 4 teachers utilized elements of high-leverage practices in an effort to teach science using engineering design. Data included 33 hours of classroom observations, semistructured interviews, and teacher reflections. Using lesson event, classroom organization, and instructional codes analogous to the literature on the engineering design process, we generated and analyzed classroom event maps, noting trends across multiple and individual teacher classrooms. Results indicated percentages of time spent on different phases within the design process among multiple classrooms as well as consistency across individual cases that demonstrate teachers' capacity to enact ambitious teaching practices through engineering design-based science instruction. Implications suggest that our approach provides a useful method to not only document and characterize engineering design-based science teaching practices but also reveals complexities of leveraging student thinking through ambitious engineering teaching practices.