A rite of passage of childhood is definitely making some GAK!  Easy to make at home and the kids love squishing and stretching it around!  For those who are unfamiliar, GAK is a little different in consistency than slime and is made with Borax instead of starch.  Liquid starch is hard to find in the regular stores around here so GAK it is!  And it’s fun!

Here’s what you need to get started:

  • Container for mixing (we used an old yogurt container)
  • Borax
  • Food coloring (We use liquid watercolors instead)
  • 4 oz Glue bottle (I’ve used Elmer’s and the one from the dollar store.  They all work!)
  • Warm water (not hot!)
  • Measuring cup
  • Measuring spoon
  • Spoon for mixingIMG_7452

Empty the entire bottle of glue into your container.

IMG_7383Fill the glue bottle with water.  Place the cap on and shake it up a bit to mix.  Then empty it into the container with the glue.IMG_7384

Add some food color if you want.

Add 1/2 teaspoon of borax to 1/4 cup of warm water.  Mix well and add to the glue mixture.


You will see that the mixture will start to blob up.  Mix it up and you will start seeing the GAK firm up.  It may look watery at first.  That’s ok.  The more you work with it, the more firm it gets.

If there is any liquid left, just pour it out (in the garbage, not the sink!)


See how stretchy it is!


The tots enjoyed playing with it!


They made hand prints with it too!  So much fun!


We placed the GAK into a baggie to take home.  I actually have my son’s GAK from 6 months ago and it’s still good!

The Science behind the Activity:

Here’s my simplistic explanation: Glue is made of a polymer which is a long chain of the same molecules all linked up together.  When you add the borax, it links up with the molecules to form a more solid substance, hence the GAK.  A common analogy is if you have a chain with repeating metal links, that can be considered as the polymer.  When you add a bunch of magnets (borax) they all clump up together like the GAK or Silly Putty.

Follow this link to see where I got the idea from and more details about the science behind the experiment: