Glue the purple and blue rubber balls together using your hot glue gun. The purple rubber balls represent neutrons, which have a neutral charge. These are bonded together with positively charged protons, which are represented by the blue rubber balls, to form the dense nucleus. Draw plus signs on the blue balls to indicate that they have a positive charge.
Straighten your wire hanger, bending it into a circle. The wire hanger will be used to represent the path of movement of electrons around the central nucleus. The ends of the hanger should not touch, so you are able to slide rubber balls through the hanger.
Thread the green rubber balls onto the hanger so the hanger runs through the ball. Force the hanger into the balls, making a small hole through the ball. Make sure the balls are spread out, since they represent electrons, which constantly move in a cloud around the nucleus. Draw negative signs on them to indicate that they have a negative charge.
Glue the 5-inch strings, one piece per side, to your nucleus. Glue the 12-inch string to the top of the nucleus. The shorter strings will be used to suspend the nucleus between the circular wire hanger, while the long string is used to hang the model up for display.
Tie each 5-inch string end to opposite sides of the wire hanger, so the nucleus is held suspended in the middle of the circular wire, electrons orbiting it. You can now use the remaining long piece of string to mount the model for public display.