Have you heard of crunchy slime and wondered what to put in slime to make it crunchy? Let’s learn how to make crunchy slime with foam balls! We have been experimenting with our crunchy slime recipes and have a few variations to share with you. Homemade slime is always a fun experiment when you try out new ideas!

Make Crunchy Slime With Foam Beads

Thick and moldable or oozy and slimy? It’s your choice when it’s time to learn how to make crunchy slime!

See an oozy crunchy slime video here!

If you have played with store-bought floam before, you are on the right path to making crunchy slime. Foam beads in either white or a rainbow of color can be added to our basic slime recipes to make an awesome floam slime.

Now, if you thought I was going to be showing you a different kind of crunchy slime with fishbowl beads, you can find our crunchy fishbowl slime recipe here!

What To Put In Slime To Make It Crunchy

For this crunchy slime recipe below, we are using foam beads. There are a variety of colors and sizes to choose from.

These beads can also be added to a modified slime recipe to make a stiffer and more moldable slime substance quite like Floam. You can read about both of these methods below and give each a try!

All of our cool, homemade slime recipes start with mastering any of our 4 basic slime recipes. Once you have practiced making slime, there are so many awesome ways to add texture, make it unique, and experiment!


Slime starts with understanding the slime activators and glue needed to make the slime substance. The chemical reaction between your slime activator and glue is how slime is formed. You can read more about the science behind the homemade slime below.


Making the best slime, starts with the best slime ingredients. We have a great list of recommended slime supplies to check out before getting started. Often people have slime failures because they aren’t using the right products. Ingredients matter!


Of course, adding fun mix-ins is the best part of making homemade slime, and that’s what we did here. It’s time to learn how to make crunchy slime two ways: slimier and thicker!

Helpful Slime Making Resources To Get Your Started

These are the best resources to look through before, during, and after making your awesome crunchy slime with foam balls! We talk more about slime science below too.

A Bit Of Slime Science

We always like to include a bit of homemade slime science around here!  Slime is an excellent chemistry demonstration and kids love it too!   Mixtures, substances, polymers, cross-linking, states of matter, elasticity, and viscosity are just a few of the science concepts that can be explored with homemade slime!

What’s slime science all about?  The borate ions in the slime activators (sodium borate, borax powder, or boric acid) mix with the PVA (polyvinyl acetate) glue and forms this cool stretchy substance. This is called cross-linking!

The glue is a polymer and is made up of long, repeating, and identical strands or molecules. These molecules with flow past one another keeping the glue in a liquid state. Until…

You add the borate ions to the mixture,  and it then starts to connect these long strands together. They begin to tangle and mix until the substance is less like the liquid you started with and thicker and rubbery like slime! Slime is a polymer.

Picture the difference between wet spaghetti and leftover spaghetti the next day. As the slime forms, the tangled molecule strands are much like the clump of spaghetti!

Is slime a liquid or solid?

We call it a non-Newtonian fluid because it’s a little bit of both!  Experiment with making the slime more or less viscous with varying amounts of foam beads. Can you change the density?

Did you know that slime aligns with the Next Generation Science Standards (NGSS)? 

It does and you can use slime making to explore states of matter and its interactions. Find out more below…

Free Printable Slime Recipe

Print off this free crunchy slime recipe sheet to get started! Look for free recipes on many of our favorite slime recipes.

Crunchy Slime Recipe

The following pictures use two of our basic recipes. For the slimier crunchy slime, I used the saline solution slime recipe. You can also use our liquid starch slime recipe or borax powder slime recipe.

For the thicker, moldable crunchy slime (floam), I used our borax powder slime recipe, but you can experiment with this saline solution slime recipe too.

Either of the two thicknesses can be made with clear or white glue. We like to use white foam beads with food coloring and white glue, and we like to use the rainbow or colored beads with clear glue. Of course, you can mix and match to make your own one of a kind slime!


  • 1/2 Cup PVA Washable School Glue
  • Slime Activator of Choice (measurements vary depending on activator)
  • 1/2 Cup Water
  • 1 Cup Mini Foam Beads (Large foam beads can also be used for a bit different texture)
  • Measuring Cups/Spoons
  • Mixing Bowls/Spoons
  • Slime Storage Containers

How To Make Crunchy Slime

Click on the recipe button below to learn how to make each basic slime. To turn it into crunchy slime, you will add 1 cup of foam beads to any basic slime recipe during the mix-ins step.

Keep reading below on how to make a thicker, more moldable floam version.

Below you can see a slimy, crunchy slime using our basic recipes from above and foam beads. The more foam beads, the denser the slime, so you can choose to use even less!

You don’t need a full cup using the large rainbow foam beads that often come in the slime supplies kit. We tried it both ways, though, and it’s up to you.

These do not make the moldable floam as nicely as the mini foam beads, so stick to adding them to the basic recipes.

Super Thick Crunchy Slime: Alternative Recipe

If you want to learn how to make crunchy slime that is super thick and moldable like floam, you want to use the borax slime recipe. We have not tested this thicker version’s saline solution slime recipe, but you can!

However, there is one change to the original borax slime recipe! The important change to the recipe is to omit the first water mixed with the glue. You will still mix your borax powder with water but not the glue.

Simply add the foam beads directly to the 1/2 cup of glue, stir, and continue with the directions. This crunchy slime will be very stiff!

Remember, the more of something you add to slime, like foam beads, the denser the slime will get.

This also means that it will potentially become less stretchy and oozy. Have fun and experiment with the ratio of foam beads to slime.

Check out the thicker crunchy slime below using white glue and clear glue with a mix of foam beads.

How To Store Slime

Slime lasts quite a while! I get a lot of questions regarding how I store my slime. We use reusable containers in either plastic or glass. Make sure to keep your slime clean and it will last for several weeks.

If you want to send kids home with a bit of slime from a camp, party, or classroom project, I would suggest packages of reusable containers from the dollar store or grocery store or even Amazon. For large groups, we have used condiment containers and labels as seen here.

We have the best resources to look through before, during, and after making your crunchy slime! Make sure to go back and read the slime science above too!

More Fun Slime Recipes To Try

If your kids love playing with slime, why not try more favorite slime ideas…

Grab the Ultimate Slime Recipe Bundle

All the best homemade slime recipes in one place with plenty of fantastic extras!

  • The Ultimate Slime Guide contains all the specialty recipes you or your kids want to make! You’ll find all the best tips, tricks, hints, and slime-y info in almost 100 pages!
  • The Ultimate Slime Holiday Guide covers all the best holidays and seasons with special themes and slime-y projects!
  • The Ultimate Borax-FREE and Taste-Safe Slime Guide shows you how to make all the best borax-free, taste-safe, and non-toxic slimes kids love, such as marshmallow slime. These recipes do not use chemical activators such as saline solution, liquid starch, or borax powder, making them truly borax-free.
  • The Ultimate Slime Coloring Book is an easy-to-print coloring book kids will love! Color and design your favorite slimes!
  • The Slime Starter Guide is a fact-filled information guide with everything you need to know to make the best slime ever!
  • Slime Science Project Pack helps you turn slime-making into a science lesson!