My oldest son, Nathan, loves science and is always asking to do experiments. His most recent interest is chemistry. So when he came home from his weekly science class with a recipe for Rubber Blubber aka Homemade Gak, to say he was excited is an understatement.
Using simple ingredients – borax, glue, and water – this recipe is fascinating to watch as two liquids come together to form a solid. Or is it still a liquid? Because homemade Gak does move! Try it with your own kids and decide for yourself!
Homemade Gak is the perfect solution to keeping kids occupied on any rainy (or too hot) day.
One word of caution – with a tiny amount of borax in this recipe, I wouldn’t let small children (who may try to eat it) play with it. Instead, I recommend making homemade playdough (also easy and can be made in less than 10 minutes.)
4 ounces school glue
4 ounces water
1/2 teaspoon Borax
1/4 cup water
food coloring (optional)
*Note: this makes a nice big bunch of Gak; you can easily half the recipe and make two different colors.
How to Make Homemade Gak in 4 Easy Steps
Step 1: Pour the glue into a small container with the 4 ounces of water…
…and mix with a spoon.
Step 2: Add the food coloring…
…and stir in well.
Step 3: Dissolve 1/2 teaspoon of Borax with 1/4 cup of warm water.
Stir until the borax is dissolved.
Step 4: Pour the borax water into the glue mixture.
This is where it gets interesting. At first glance, it may look like your Gak experiment has failed, but stir it up and you’ll see the magic….er chemistry…happen.
Stir the gak until it’s become more solid and is forming around the spoon. Watch and be amazed. It is really cool.
I recommend waiting to handle it until the food coloring is well mixed in. Nathan was a little eager to start playing with his homemade Gak and ended up with slightly blue hands. That and he got excited and added a little too much food coloring to start with. Somehow that shouldn’t have surprised me.
Kids can do so many fun things with Gak. Did you know it will bounce?
At the same time, it will slowly spread.
Have fun making homemade Gak with your kids!
Watch this video, Nathan and I made where he explains more about Gak, also called Rubber Blubber, and demonstrates how it can do cool things, like bounce:
Click here for the printable recipe: