Punch two holes in a small paper cup. Use a pencil to poke a hole into the bottom. Wiggle it to widen the hole. Remove the pencil.
Trim off the sides of another paper cup. Cut off ⅓ of a paper straw. Glue the short straw piece to the bottom of the trimmed cup.
Trace a quarter on thin cardboard. Cut it out. Punch a hole near the edge of the circle.
Fold a chenille stick in half. Push it (doubled) through the leftover (⅔-length) piece of straw.
Place the follower inside the base with the straw sticking out of the bottom hole.
Bend the straw, as shown in the video. Push the axle through one of the side holes. Slide the cam over the axle.
Push the axle through the other side hole. Bend the chenille-stick end so the axle stays in place. Center the cam.
Use markers to draw shapes on cardstock. Cut them out. Glue or tape them on top of the follower and the base.
How to Play
Hold the base in one hand, and the axle "crank" in the other. Turn the axle crank, and the follower will move up and down. Learn Its Secret:
A cam is a mechanism that changes spinning motion into straight motion by pushing an object that rests on it (the follower) in one direction. Cams are used in toys, cars, machinery, and electric toothbrushes.
