Application of Threshold Concepts to Improve a Design-Focused Course in Transportation Engineering

Design is an integral part of engineering courses. To address its associated problems, however, is a challenging task in instruction because of design's open-endedness and complexity. In this study, two theoretical models were implemented in an introductory transportation engineering course to address the challenges associated with design of a highway. First, the theoretical framework proposed by the threshold concepts model was used to identify a candidate concept for the instructional redesign process. Two major characteristics of threshold concepts, integrativity and transformativity, were used to identify horizontal alignment as a candidate concept for the highway design process. Second, concept mapping was done to create operational measures of the integrativity of complex concepts, such as horizontal alignment. These maps and measures led to several changes to the structure of lecture materials and project tasks. Finally, questions for reflective assessment were administered to students after each redesigned instructional task and at the end of the course to find evidence of the potential transformativity of the proposed instructional changes. Implementation of the above-mentioned theoretical framework allowed the instructor who participated in the study to successfully streamline the instructional process and benefitted student perceptions and attitudes about learning highway design.