Student pairs design and construct small, wind-powered sail cars using limited quantities of drinking straws, masking tape, paper and beads. Teams compete to see which sail car travels the farthest when pushed by the wind (simulated by the use of an electric fan). Students learn about wind and kinetic and renewable energy, and follow the steps of the engineering design process to imagine, create, test, evaluate and refine their sail cars. This activity is part of a unit in which multiple activities are brought together for an all-day school/multi-school concluding “engineering field day” competition.