A low-cost materials laboratory sequence for remote instruction that supports student agency

Abstract Under the new ABET accreditation framework, students are expected to demonstrate "an ability to develop and conduct appropriate experimentation, analyze and interpret data, and use engineering judgment to draw conclusions" (ABET 2019). This outcome must be operationalized and assessed in the form of concrete performance indicators. Traditional, recipe-based labs provide few opportunities for students to engage in realistic experimental design, and recent research has cast doubt on their pedagogical benefit (Holmes, et. al. 2018). At the same time, the COVID-19 pandemic has forced institutions to move to virtual and geographically distributed learning. To address these challenges we developed a series of online materials testing labs for an upper-division mechanics of materials course. The first three labs consist of video demonstrations of traditional lab experiments coupled with group discussions and data analysis. Two of these "traditional" virtual labs are supplemented with generative activities in which students recreate and demonstrate standard mechanical tests with household items in a peer-teaching video format. The final lab is a guided-inquiry activity focused on experimental design. Using only materials available at home, students measure the Young's modulus of an aluminum specimen that they prepare themselves and use their results to design a hypothetical product made of the same material. In order to provide the same opportunity for students around the world, the test specimen is taken from a standard aluminum beverage can. One measure of whether or not an activity supports student agency is the diversity of solutions generated by students (Willner-Giwerc et. al., 2020). We analyzed all 44 reports from the final guided-inquiry lab and coded the experimental procedure on five critical decisions including the type of experiment performed, geometry of the specimen, loading method, measurement method, and additional strategies used for increasing measurement precision. We identified 31 unique approaches to the problem, with no one approach accounting for more than three submissions. Student outcomes were measured by a short survey of students' feelings of agency and self-efficacy administered directly after every lab activity except for the first one. The fraction of students endorsing statements related to a sense of control increased dramatically between the "traditional" labs and the guided-inquiry lab: from 51% to 81% for goal-setting and from about 67% to 93% for choice of methods. Students' self-efficacy increased significantly in the primary targeted skills (designing experiments, making predictions, and generating further questions), but there was no significant shift in skills not explicitly targeted by the guided-inquiry lab (equitable sharing of labor, expressing opinions in a group, and interpreting graphs). While a true control group does not exist for this study, the increase in targeted skills coupled with the lack of increase in important-sounding but non-targeted generic skills provides some evidence for the effectiveness of the guided-inquiry intervention. Our experience demonstrates that at-home lab activities can achieve sophisticated learning outcomes without the use of lab equipment or expensive standardized kits.