As an in-class warm-up for the recycling project I made a "Reverse Yo-Yo" out of rulers, tubes and various cords and string. It is used by pulling the shoelace as one would a lawnmower and the cylinders spin to rewrap the shoelace.
I started by cutting slots in the smaller cylinder and inserting the rulers through the slots creating an X shape to create the stand. I kept the larger cylinder between the ruler slots to keep the cylinders together.
I then tied leather cords around the larger cylinder to create a stationary point to tie the shoelace to without damaging the surface of the material. I also tied 2 more leather straps to the sides to make rails so the string would not slip off the sides when pulled.
Lastly I attached a handle to the end of the shoelace for easier use. The handle also helps with easier storage by inserting the handle between the two cylinders.