Developing conceptual knowledge situated in engineering practice has been identified as a priority by national leaders in engineering education, with the theoretically-founded expectation that it will result in students who are more capable of innovative engineering design. Progress toward this goal requires understanding fundamental ways of knowing and learning of both engineering students and engineering practitioners, coupled with the design of research-based curriculum. The goals of this research are to synthesize early career professionals' and students' mental models of traffic signals and use this knowledge to develop a fully validated traffic signal concept inventory (TSCI) along with a set of ranking task exercises in traffic signal operations relevant to engineering practice. This will be the first development of a concept inventory and conceptual exercises using engineering practitioner knowledge. This work will: 1) Determine core concepts for isolated traffic signals, coordinated traffic signals, and systems of traffic signals; 2) Synthesize student and practitioner conceptual understanding of these traffic signals; 3) Develop a situated concept inventory and ranking tasks for traffic signals; and 4) Implement the TSCI and ranking tasks at 12 universities throughout the US and actively disseminate the research results. In the first year of implementation hundreds of students will be assessed with the validated TSCI. This study is significant because it advances the field by identifying differences in conceptual understanding between practicing engineers and students and develops a concept inventory instrument and conceptual ranking exercises incorporating practitioner understandings.
