Smooth Cruise STEM Challenge: Forces are the pushes and pulls in our world. By providing pushes and pulls, forces help to get and keep things moving. As you would expect, it also takes energy to provide the forces needed to move stuff. The aerodynamics of a car depends on how much air the car has to move out of the way as it travels. The more air it has to move, the more drag, or resistance, there is to the forward motion of the car. In this STEM Challenge, your task is to build an aerodynamic car that can move down a track as smoothly and quickly as possible. Key Concepts: forces, energy, pushes, pulls, aerodynamics, drag.