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How to Make the Prettiest, Easiest Rainbow Slime

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Nothing says happy like a pretty rainbow. And this amazing rainbow slime will be a HUGE hit in your science classroom, or just at home! Keep reading to learn how to make rainbow slime.

We love slime recipes. It’s one of our favorite things to make. Slime is fun because it is always impressive to see molecules bonding together in a new way right before your eyes.

Plus, who doesn’t love playing with a magic, stretchy slime rainbow?

this amazing rainbow slime will be a HUGE hit in your science classroom, or just at home! Keep reading to learn how to make rainbow slime.

We’ve found that the best slime recipe doesn’t use Borax powder (although we’ve made some cool slimes with Borax!), but rather with laundry starch (laundry starch does contain Borate though, so don’t use this recipe if you are sensitive to Borate chemicals).

You can buy a huge container of starch that will last you a LONG time.

The only way to make slime more fun is to bring in more color. A LOT more color. And so, rainbow slime recipe is born.

How to Make Rainbow Slime

Nothing says happy like a pretty rainbow. And this amazing rainbow slime will be a HUGE hit in your science classroom, or just at home!

More Slime Recipes to Try!

Read on to see how to make the very best rainbow slime! And don’t forget to try these other colorful slime recipes: unicorn poop slime, galaxy slime, and tie dye slime!

Glue and Starch Slime Science

this amazing rainbow slime will be a HUGE hit in your science classroom, or just at home! Keep reading to learn how to make rainbow slime.

Slime is made when boron mixes with the polymer chains in the glue, creating strong, but flexible bonds between the molecules. 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.

If you want to make this into a full STEAM activity, try mixing glue with other ingredients to see if you can make slime in other ways. You can also try mixing colors of slime together.

What new colors can you make?

DON’T MISS: THE ULTIMATE LIST OF SLIME RECIPES!

Rainbow Slime Recipe Tips

slime rainbow

If this is your first time making slime, you should follow along with our post on slime troubleshooting.  Luckily,liquid laundry starch slime made with clear glue is the easiest slime recipe. You can make this slime using white glue or clear glue, for slightly different effects.

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).

Easy Steps to Make Rainbow Slime

rainbow slime recipe

Follow these directions and you’ll have the best rainbow slime ever!

This Borax-free slime is fun for all ages (except for babies who might eat it).

Disclaimer: This post contains affiliate links at no cost to you for your convenience. 

slime science lesson

Rainbow slime ingredients:

Elmer's Liquid School Glue, Premium Clear, Washable, 1 Gallon, 1 Count - Great For Making SlimeElmer’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) BottlesFood Coloring Liqua-Gel – 6 Color Rainbow Kit in .75 fl. oz. (20ml) BottlesPurex Sta-Flo Liquid Starch, 64 OuncePurex Sta-Flo Liquid Starch, 64 OunceOriginal Stationery Arts and Crafts Glitter Shake Jars, Extra Fine, 24 Multi color SetOriginal Stationery Arts and Crafts Glitter Shake Jars, Extra Fine, 24 Multi color Set

Easy Rainbow Slime Recipe

rainbow slime science experiment

First add 1/2 a cup of water to each mason jar. Put a squirt of color into each jar (red, orange, yellow, green, blue, and purple). Mix.

Making rainbow slime. Pouring white glue into mason jars.

Add one bottle of glue to each jar and stir until combined. Or, if you buy a gallon of school glue (which you’ll want if you make slime a lot, so much cheaper!), put 1/2 a cup of glue in each jar.

Pour 1/2 a cup of laundry starch into each jar.

Kid hands stirring jelly rainbow slime.

Stir with a fork until the mixture starts to form stretchy, polymer bonds. It will sound like a dog lapping when it’s about ready.

Girl pulling yellow rainbow slime out of a jar.

Wait 10 minutes for the glue and starch to fully bond. This will prevent your hands from getting as sticky.

Colorful rainbow slime.

Place one clump of each color in the order of the rainbow: Red, orange, yellow, green, blue, and purple!

Kid hands holding red, orange, yellow, green, blue, and purple rainbow slime.

Stretch and play with this amazing rainbow slime! Just watch out, if you mix all the colors together it becomes an ugly brown.

Nothing says happy like a pretty rainbow. And this amazing rainbow slime will be a HUGE hit in your science classroom, or just at home!
slime science lesson

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