Magnetic Slime

(Chemistry for ages 5+)


What better activity is there when you’re cooped up at home than making silly putty? There are so many ways to make silly putty even more fun, like making it change colors at different temperatures. The video above shows another cool way to experiment with slime: making it magnetic. Here’s how:


Elmer’s white glue (4-ounce bottle)
Corn starch
Iron filings
Magnets – different sizes and strengths make it more fun!
Adult supervision (Adult supervision at all times please)
**Day before preparations

  1. First, you need to make the silly putty. The first 4 materials listed are needed for one of the many ways to make slime, but you can use whichever recipe you prefer. The next 4 steps will show you one of those ways, but if you are using a different recipe, jump to step 6 for the rest of the activity.
  2. Add the whole 4-ounce bottle of Elmer’s white glue to a bowl.
  3. Add ¼ cup of cornstarch to the glue and mix.
  4. In a separate bowl, add ¼ cup of very hot water and stir in ¼ teaspoon of Borax until it dissolves.
  5. Add the water and Borax mixture to the glue and stir. It will start to clump up, so using your hands to knead the mixture together works the best.
  6. Flatten the silly putty and sprinkle some iron filings over top and fold it in.
  7. Again flatten the silly putty and sprinkle more iron filings over top. Fold it all together and mix the iron in really well. The putty will turn dark and have a dirty appearance, but this is just because of the iron.
  8. Time to play with some magnets! The video shows many different ways you can manipulate the slime with different types of magnets. Have some fun and see what you can come up with!



Iron is a ferromagnetic material, meaning it is attracted to magnets. When the iron filings are mixed into the slime, it takes on the ferromagnetic properties of the iron. Magnets are made of a material that are formed with a permanent magnetic field that exerts an attractive force on the ferromagnets, like iron and some other metals.