Traffic congestion and road tolls are familiar economic concepts for most undergraduates; however, students often have difficulty explaining exactly how theoretical principles like externalities and social welfare are related to their real-world experiences, such as driving. The authors present a classroom exercise to demonstrate how congestion externalities are generated, the effects on private and social welfare, and how appropriately priced tolls can address congestion externalities. Students are asked to evaluate outcomes in five different driving scenarios, with and without congestion or tolls. The authors offer discussion questions to make the activity engaging and informative. They report the results of their efforts to administer the exercise. This 75-minute exercise is appropriate for introductory or intermediate microeconomics, political economy, or environmental economics classes of various sizes.