Investigating optimization as a practice in a middle school engineering class (work in progress)

This work in progress paper describes a pilot study intended to better understand the ways students and teachers in a middle school engineering class iteratively optimize a multi-objective problem. Recent reforms in STEM education have placed an emphasis on engaging K-12 students in the knowledge-building practices of professionals as a way to teach and apply content, but so far few have looked closely at classrooms engaged in these practices. An ethnographic perspective was used to closely observe the talk and actions of three groups of eighth-grade students from a low-income rural school district and their teacher as they attempted to minimize cost, mass, and deflection of a truss cantilever using two computer-based tools. Methods of interactional ethnography were used to analyze the ways in which they took risks to test the boundaries of the structure and balanced tradeoffs while still producing a physical prototype that could hold a 1.5 kg mass. Preliminary results suggest that when supported by their teacher, students became increasingly more comfortable with taking risks and pushing the limits of the structure in low-stakes situations. Additionally, we found that students were able to use a variety of approaches to strategically remove structural members, including applying scientific knowledge, and were able to appropriately compare multiple models to inform the design of their physical prototype. To our knowledge, this is the first study to investigate optimization explicitly as a practice in a precollege context, and it contributes to the knowledge base of our understanding of how students and teachers do engineering and how engineering educators can promote improved curriculum and pedagogy in this area.