PINE-DESIGN helps improve the performance of a Pinewood Derby car by asking questions about the car and suggesting ways to make the car faster. To acheive this, PINE-DESIGN considers the weight of the car and wheels, the rotational inertia of the wheels, the friction between the wheels and axles, and the aerodynamic drag of the car. To get the most from PINE-DESIGN, the user needs a scale to weigh the car and a set of calipers to measure the wheels.