The impact of principle-based reasoning on hands-on, project-based learning

Prior research suggests that experts and novices employ markedly different approaches to engineering design tasks. For example, novice designers commonly use trial and error, which researchers liken to backward-reasoning. Experts use forward-reasoning, which allows them to accurately predict the impact of certain decisions. In this paper, we present a complementary conceptualization for how experience affects design approaches. We liken backward-reasoning to example-based reasoning, and forward-reasoning to principlebased reasoning. In study 1 (N=13) students complete an engineering design activity. A qualitative analysis shows clear instances of example-and principle-based reasoning strategies. Study 2 (N=20) compares the efficacy of the two approaches by using a between subject design. We find that principle-based reasoning improves the quality of designs (p < 0.01) and learning of important engineering principles (p < 0.001). This suggests that handson learning environments may benefit from encouraging students to employ principle-based reasoning.