In this lesson, students become bioengineers, trying to effectively and safely restore “blood flow” through a model clogged artery. Background work, including dissection ideas, provides students with an understanding of circulatory system anatomy; it also piques their interest in heart disease and current technologies to combat it. The teacher establishes a problem: blockage of a coronary artery! Students see the model clogged artery (frosting in a plastic tube) and come up with ideas for clearing the artery, also generating goals and constraints for the process. With a set of pre-determined materials, students create and test their method of clearing the artery, done by pouring water through the tube and measuring flow rate. Students then evaluate project designs, peer-review each other’s work, modify designs, and retest. Wrap-up (assessment) is done through a report or poster-session, and students argue for which designs are best based on evidence in relation to the established criteria.