This is just a small cannon which can fire at least three small green/black rods a good ten feet.
Step 1: The Base
A semi-circle and circle snapped together with rods connecting them.
Step 2: Adding Onto the Base
Two yellow rods vertical and one horizontal for both sides, don't worry about connecting them.
Step 3: The Things That Hold the Barrel in Place
Make sure that the green rods are facing up when you pull up the two holders.
Step 4: Connecting the Other Side.
Step 5: Making the Barrel.
Only put the blue washers on one side of the barrel (as shown). It saves pieces.
Step 6: Making the Pusher Thing.
Slide the rubber band through the middle hole on the yellow semi-circle and attach the rubber band to the green rods on the barrel holders.
Step 7: Pictures of What It Should Look Like When Small Green Rods Are in the Barrel and Where to Put the Last Washer.
Put the washer between the first two red connnecters when the pusher thing is fully pulled back (not all the way out) so that it will stop the pusher thing from shooting forward.