Making a spiral marble machine out of cardboard is a fun and easy project that can be done with just a few simple materials. First, you will need to gather cardboard, scissors, tape, and marbles. Begin by cutting out two identical rectangles from the cardboard. These will be the sides of the machine. Next, cut out four identical triangles from the cardboard. These will be the supports for the spiral track. Tape the triangles to the sides of the machine, making sure that the points of the triangles are facing up. Now, cut out a spiral track from the cardboard. This can be done by cutting a long strip of cardboard and then curving it into a spiral shape. Tape the spiral track to the triangles, making sure that the track is securely attached. Finally, place the marbles at the top of the track and watch them spiral down the machine. Enjoy!