Making a pen-rubber band shooter is very simple and you require very less material.
MATERIALS REQUIRED :-
1. A PEN THAT CAN BE OPENED FROM BOTH SIDES
2. A SAFETY PIN
3. AND TWO RUBBER BANDS
Step 1: REMOVE....
Take out all the parts of the the pen i.e. the two front cap, the refill, end cap.The inner front cap and the end cap are of no use.
Step 2: JUST MAKE IT...
Take the main cap of the pen and just place at the top of the pen and wrap it with rubber band.
Now take the other rubber band and attach it to the cap. Now take the safety pin fix in the second rubber band
(REFER TO THE PICTURE)
Step 3: OVER...
Just fill the refill by putting the refill in the pen and then fix the refill in the safety pin, then it is ready to shoot.
You can also take out or cut the upper end of your cap, it can be used to aim things