Build a joystick that can turn on and turn off multiple things
Build a helicopter that flies at least ten feet in the air and stays up for three seconds while carrying one penny.
Design a robotic arm that can move a marble, a straw, and a washer from the table into a cup without using your hands.
Build a lightweight wing structure that is 12 inches long and can hold up a heavy load (weight) without deflecting.
Build a satellite with a 6-inch square body that can deploy its own solar wings and antennae, and can fit inside a 9-inch diameter tube.
Build a plane that is powered by stored energy from a rubber band, balloon or spring. The plane should be able to fly straight for 5 feet.
Make a cantilever that can hold 5 marbles at least 12 inches away from its base structure.
Build a 3-D object out of tetrahedra that is as big as you are.
Make pieces for a structure that builds itself using magnets.