Things You'll Need
Instructions
Paint 14 Styrofoam balls one color and 14 another color. These are the protons and neutrons. Since silicon has so many protons and neutrons, it is a good idea to use small Styrofoam balls to keep the model at a manageable size.
Glue the Styrofoam balls together to form a ball, mixing the protons and neutrons. Use a plain white or craft glue. This is the nucleus of the atom.
Cut 14 thin dowel rods with scissors or a craft knife -- two short, eight medium and four long. Push the ends into the nucleus, distributing them evenly. If you want to use this model with other models of atoms to demonstrate how molecules form, you may want to use wire instead, which will be easier to repeatedly remove and put into different locations on the nucleus than a dowel rod.
Glue a pompom to each the end of each dowel rod. These are the electrons. The different lengths of the dowel rods put each pompom electron into its correct general orbit on the atom.
Make a small loop from wire and insert it into the nucleus. This addition will enable you to hang the model, if desired.