Build a Mars rover that can travel using elastic energy.
Design and build a paper bird that can glide at least 6 feet.
Create a simple machine that transfers motion from one straw to another using a belt. Make sure the direction of your motion remains the same.
Build a device that will carry a seed at least 3 feet from where it is launched.
Design and build a powerful bird wing that can spin you around in an office chair when you flap it.
Build a skyscraper that stands strong in the wind and is at least 18 inches tall.
Build a sailboat that is powered by the wind.
Build a submarine that will dive down through the water and come back to the surface.
Build a boat that can hold as many pennies as possible.