Before today, I had never attempted to make homemade slime. It seemed like it would be intimidating and take along time. But, it turns out, how to make slime with borax is quite easy!
Making a slime recipe with borax is one of our favorite ways to teach kids about chemical bonds and makes a fun slime science experiment for kids!
How to Make Original Slime
Since this first attempt at slime, we have made tons of other versions! This version is made with Borax, and is the classic Borax slime that most people think about when you think about homemade slime.
But there are a lot more ways to make slime! You can see all our slime recipes in one place here.
Check out the full list of summer slime recipes!
If you are ready to take on the challenge of homemade slime here is how we did it:
The Original Slime Recipe with Borax
Borax slime is one of the best slime recipes because it is easier to make than many of the common variations. Borax slime also lasts longer, which means you can keep playing with it for weeks, rather than just a few days.
When borax slime gets too sticky, you can add a bit more of the borax liquid to the slime and return it to its original stretchiness!
The Science Behind Making Slime
Slime is made when boron mixes with the polymer chains in the glue, creating strong, but flexible bonds between the molecules. This bonding process is known as crosslinking.
Crosslinking creates molecular bonds that are crossed like a thatch roof, rather than in one long segment like a chain.
Slime forms when polyvinyl alcohol and borate ion mix. The polyvinyl alcohol is attracted to borate ion, which causes them to form long chain molecules.
When this reaction occurs, the two separate materials mix and slime is formed.
There are so many fun tweaks you can make to a basic slime recipe, like my kid’s favorite, fluffy slime!
Since this slime does contain borax, if you have a sensitivity to it, you may want to try our baking soda slime instead.
Slime Tips and Tricks
If you don’t want to waste a lot of ingredients, try mixing up a small batch first to make sure you won’t have to tweak it before you make the larger version.
We always stock up on gallon sizes of glue and the large laundry starch just in case something goes wrong (but it almost always goes smoothly).
How to Make Slime Out of Borax
Follow these directions and you’ll have the best slime with clear glue and borax!
The Foolproof Slime Recipe
Follow these simple directions to make the original Borax slime!
This post contains affiliate links.
Elmer’s Liquid School Glue, Premium Clear, Washable, 1 Gallon, 1 Count – Great For Making SlimeFood Coloring Liqua-Gel – 6 Color Rainbow Kit in .75 fl. oz. (20ml) BottlesPurex Sta-Flo Liquid Starch, 64 OunceOriginal Stationery Arts and Crafts Glitter Shake Jars, Extra Fine, 24 Multi color Set
Borax Slime Safety Warning
Make exactly according to this recipe, we haven’t had any problems with slime causing allergic reactions or skin burns. However, some individuals may be more sensitive than others.
Don’t let kids play with this slime recipe if you notice any ill effects. Additionally, only make this version of slime if your kids will not put it in their mouths. Borax powder (and glue) should not be consumed.
Borax Slime Directions
Mix about ½ a cup of water and a teaspoon of borax until the borax dissolves.
My kids love sparkly things, so we added glitter, but if your kids don’t like sparkles as much, just add color. Add 1/2 a cup of water to the glue mixture.
Pour the borax mixture into the glue mixture. Stir for a few seconds with the spoon, then use your hands for the rest of the mixing.
We thought our slime would be really oozy, but it turned out stiffer than we thought it would. This is because Borax slime produces a stiffer consistency when used with clear glue.
If you use it with white glue, it will be a little more flexible.
However, it will never be as flexible and stretchy as laundry starch slime, which is why we prefer using laundry starch for our slime.
When you pull the slime slowly, it stretches like hot cheese. When you pull it quickly, it breaks apart like cold cheese.
The girls loved squishing the slime, watching the pieces reform into a solid whole, and in Bo’s case, she loved crumbling our slime into tiny pieces.
Don’t forget to check out the other posts in the 31 days of STEM activities for kids series!