Guided inquiry laboratory exercises designed to develop qualitative reasoning skills in undergraduate engineering students

We describe inquiry-based lab exercises designed to develop qualitative reasoning skills. The exercises require students to predict outcomes before making measurements, and to compare predictions to measurements as soon as those measurements are available. The predict-then-confirm process aims to develop both qualitative and quantitative reasoning as a practical engineering skill and as a method of gaining deeper understanding of the material. Qualitative reasoning involves the use of engineering models and formulas to draw conclusions without resorting to numerical computation. In this paper, examples of qualitative reasoning are demonstrated for measurements on a kitchen blender and a toaster. Because this equipment familiar to students and has readily understood operating principles, qualitative reasoning can be introduced as a way to extend common sense ideas about how and why the equipment works.