Gravity is the force that makes things fall to the ground, but what allows some things to fly or float? Why does a piece of paper float lazily to the ground, while the same piece will drop straight down if it’s crumpled into a ball? Birds, kites, and pieces of paper all have large surface areas to “push” against the air — resisting the force of gravity. In this exercise, students designed and constructed “flying machines” to see if they could create objects that would use surface area to maximize “take off speed”, glide distance, or float times. After testing their designs by shooting them up a vertical wind-tube (powered by a leaf blower), they went back to the drawing board to see how they could improve their creations.