2023 ASEE Annual Conference & Exposition

Courses and labs commonly reinforce learning through activities that explore applications, but it remains vital to promote deeper conceptual understanding. Also, with increasing class sizes, it has become more difficult to monitor the conceptual understanding of individual students. To address these issues, we have developed a framework for implementing short and individualized activities that focus on bridging the gap in conceptual understanding of a key topic. The framework involves administering a demonstration in a fun and exciting way while connecting independent concepts first introduced in the classroom. Specifically, we designed a demonstration for a mechanics and materials lab to aid in understanding a material’s behavior during loading and failure and how temperature can affect a material’s response. The demonstration requires students to think critically and draw connections in the interplay among mechanical loading, material behavior, and failure behavior, as opposed to simply assuming that failure behavior is always correlated with the material type itself. The demonstration consists of two mini activities: in the first activity students break chalk and observe failure surfaces expected for a brittle material and in the second activity a polymer is cooled with liquid nitrogen, a torsional load is applied until failure, and the failure surface is compared to that of chalk. Students’ understanding gained from this demonstration can easily be applied to other topics involving failure behavior in the course. These types of short demonstrations could be used in any lab or even as a quick way to grasp concepts during classroom lectures. Students were split into a study group (n=155) who attended the activity and a control group (n=162) who did not attend. Three assessments were conducted: an initial impression survey, a quiz on the concepts targeted, and a final extensive feedback survey. Surveys show that students had an overwhelmingly positive attitude toward the activity with perceived improvements in their learning. The study group’s performance in the quiz was found to be statistically significantly better using a one-tailed t-test with a significance level of α=0.05, t(315) =3.428, p<.001. A second demonstration using the established framework was added in the second run of the study and focused on the connection between the intrinsic coefficient of thermal expansion and the interatomic energy potentials of a pair of bonded materials. The preliminary results of the second run show comparable results for students’ initial impressions. The results demonstrate that the framework developed for implementing short, low-cost, and engaging demonstrations had a positive impact on student’s performance and learning.