This article describes the steps incorporated to teach an engineering design process in a fifth-grade science classroom. The engineering design-based activity was an existing scientific inquiry activity using UV light--detecting beads and purposefully creating a series of engineering design-based challenges around the investigation. The fifth-grade students were to use evidence from their inquiries to form their designs. During this process, models for the engineering design process were reviewed, along with the seven essential features for teaching engineering design. The features were identified as being: (1) client-driven and goal-oriented; (2) providing an authentic context; (3) incorporating constraints; (4) using materials, resources and tools that are familiar to students; (5) requiring the solution to be an artifact or process; (6) yielding more than one solution; and (7) involving teamwork. These features aligned well with each design task implemented. To assess students' engagement in the engineering design process, a rubric was developed that aligned with the essential features of design. Depending on where students were within a design task, a teacher could identify one or more engineering practices from the rubric and assess students accordingly. These features motivated students through real-world situations and challenged them to chart their own course of action while applying science concepts and fostering a sense of curiosity, innovation, and collaboration. These features also provided a usable framework for teachers to craft their own engineering design-based tasks, related assessments, and cross-disciplinary activities.