Bouncing Polymer Balls

This post was actually scheduled for yesterday, however I forgot to hit publish so it is a day late.

We are half way through this weeks post of science related projects. Today we are actually redoing a project we attempted a few months ago that didn't work out so great, and you can read about it here. TIP: It actually helps if you read ALL of the directions BEFORE starting. Just saying :)

So today we will be making bouncing polymer balls. First you will need to gather all of your materials:

• borax (found in the laundry section of the store)
• cornstarch (found in the baking section of the store)
• white glue (e.g., Elmer's glue - makes an opaque ball) or blue or clear school glue (makes a translucent ball)
• warm water
• food coloring (optional)
• measuring spoons
• spoon or craft stick to stir the mixture
• 2 small plastic cups or other containers for mixing
• marking pen
• watch with a second hand
• metric ruler
• zip-lock plastic baggie

 I used 2 different types of cups so I knew which cup would have the borax solution in it and which one would have the ball mixture in it. It is best to use shorter cups with a wider mouth if possible. If you are doing this with multiple children, each child will need 2 cups. These instructions will only make one ball.

In the first cup add 2 tablespoons of warm water and 1/2 teaspoon borax. Stir until the borax has dissolved and add food coloring at this time if you wish.



In the second cup pour 1 tablespoon glue, 1/2 a teaspoon of the borax mixture from the first cup and 1 tablespoon cornstarch. DO NOT STIR THEM TOGETHER. Instead allow the ingredients to interact on their own for 10-15 seconds before stirring. Make sure you stir the mixture well until it becomes impossible to stir it anymore. Take it out of the cup and start molding it into a ball in your hands. The ball will start out sticky but will solidify as you continue to work with it.

Once the ball is no longer sticky go ahead and bounce it! You can store the bag in the ziplock baggie to prevent it from drying out once you are done playing with it.