• Borax
• 8 ounce bottle of school glue
• Large mixing bowl
• 2 spoons for mixing
• Plastic cup
• Measuring cups (1/2 cup, 1 teaspoon)
• One zip-lock bag
• Iron powder (iron filings or staples can be used as an alternative)
• Neodymium magnet
• Tap water
1.
Open the bottle of school glue and empty it completely into the large mixing bowl
2.
Fill the empty bottle of school glue with water, tighten the lid, and shake it up for about 30 seconds
3.
Pour the water from the bottle into the large mixing bowl
4.
Add 8 tablespoons of iron powder (or a handful of iron filings or staples) to the large mixing bowl and stir well with a spoon
5.
Measure out 1/2 cup of tap water and pour it into a plastic cup
6.
Add 1 teaspoon of Borax to the plastic cup, and stir it together using a spoon
7.
Add the borax and water from the plastic cup to the large mixing bowl
8.
Mix up everything in the bowl very well

9.
Hover the neodymium magnet over the slime, and watch as the slime follows the magnet!
Why is the slime following the magnet? It all has to do with magnetic attraction!
The secret ingredient that makes the slime magnetic is the iron oxide, which is attracted to the neodymium magnet.
When the school glue, borax, and water are all combined together, they form a slime-like material known as a polymer. Polymers are long chains of molecules that act similarly to gum. When you chew gum, it becomes very flexible because all of the molecules are able to slide against each other easily. When you are done with the gum and spit it out, it becomes sticky. Polymers work in a similar way. If the molecules can slide past each other easily, then the substance acts more like a liquid, but if the molecules stick together, it will act more like a solid that you can pull and stretch.
In this experiment, why doesn’t the iron fly right out of the slime? Adhesion and cohesion are key. Adhesion is the force that holds molecules of different substances together (the iron and the slime), and cohesion is the force that holds molecules of the same substance together (slime molecules). This allows you to move the neodymium magnet all around the slime to make fun shapes
and designs in any section of the slime!