Make your own rubber ball.
You can make your own rubber ball with Borax and glue and other ingredients you might already have around the house. This fun scientific experiment yields a bouncing rubber ball that can be colored with common food coloring.
1. Mix 1 tbs. of Borax into 1/2 cup of warm water in a plastic cup. Stir with a craft stick until mostly dissolved. Often some powder remains on the bottom undissolved. This is normal.
2. Put 3 tsp. of plain white glue in another cup. Using a clean stick, stir in 2 to 3 drops of food coloring. Mix well. Try combining drops of different colors for more variety.
3. Pour the glue mixture into the Borax solution. The glue mixture will begin to thicken immediately. Stir with a stick as long as possible but do not leave in the solution too long. The mixture’s consistency will improve as you knead it.
4. Pick the solidified glue mixture up out of the Borax solution once it is too thick to stir. Knead the solid material with your hands. If the mixture remains too sticky, dip the mass back into the Borax solution briefly and continue to knead until you are able to form a bouncing ball shape.
5. Store your rubber ball made with Borax and glue in a plastic bag or plastic storage bowl with a lid.