Learn How to make Oobleck without cornstarch in 5 minutes! A fun science experiment for kids to introduce basic concepts about fluids like liquid and solid and have the most fun sensory play activity.
Oobleck is scientifically known as a non-Newtonian fluid. Let me explain.
Ask yourself, is Oobleck solid or liquid? Well, it’s none of the above. It’s, in fact, both at the same time! This is what we call a non-Newtonian fluid.
It simply means that this material acts like a liquid when you don’t apply pressure on it, like when holding it in your hands.
But, it hardens and acts like a solid if pressure is applied to it. If you press it with your fingers or hands, it’s hard and difficult to grab.
In fact, if you make enough of it, you can run on it without getting your feet dirty or wet! If you were to stop running, though, you’d sink!
How do you make Oobleck?
Before I share the option to make oobleck without corn starch, let me share with you the basic instructions to make classic oobleck at home.
The classic recipe is made with a combination of:
- 1 1/2 cup of cornstarch or cornflour – both work with the same amount. This refers to the regular corn starch from the baking aisle of your grocery store, nothing fancy.
- 1 cup water
- Drops of food coloring if you like – optional, just for fun!
Then, mix the cornstarch with cold tap water and add your food coloring (if used).
Mix by hand until the mixture of cornstarch starts to harden when squished but drips like honey when you release the pressure.
But if you’re out of cornstarch at home, you are probably wondering which flour can be used to replace the cornstarch to make Oobleck.
We made our Oobleck with arrowroot flour and made an Oobleck pool in a large plastic container. Since Halloween is coming up, we made spooky oobleck by adding plastic googly eyes to the mixture.
There are actually three other flours that work really well to make oobleck. However, since these flours have different properties than cornstarch, the flour to water ratio is different.
Read my How to make oobleck without cornstarch instructions below to make sure your oobleck comes out great.
- Arrowroot Flour
- Tapioca Flour also called tapioca powder
- Potato Starch
The first two flours work with the same ratio. You may have to adjust the ratio for potato starch.
Can I make Oobleck with all-purpose flour?
Unfortunately, you can’t make Oobleck with wheat flour.
You absolutely need starchy flour, like arrowroot flour, corn starch, cornflour, or potato starch.
Oobleck Frequently Asked Questions
Sometimes Oobleck doesn’t come out as you expect, but the good news is that you can always fix Oobleck!
And even if it ends up like Oobleck-slime because you added too much water, kids still have fun with it.
Can I save hard Oobleck?
You can always save a too-hard Oobleck by adding more cold water. Always add water 1 tablespoon at a time to avoid a fast dilution of the Oobleck recipe.
What to do if my Oobleck is too liquid?
To save a watery Oobleck texture, just add more of your starchy flour. Add it slowly as the texture can change very quickly.
However, you can also make Oobleck-slime by adding more water to the mixture. It’s not quite the same, but it’s just as fun!
Is Oobleck edible?
No, you can’t eat oobleck. Cornstarch or any starchy flour are not edible raw flours. Raw cornstarch leads to anemia and other health issues.
Make sure you play oobleck with your kids and don’t let them eat this.
Can you make Oobleck with baking soda?
You can’t make oobleck with only baking soda. You will have to use some starch or baking powder – which is basically baking soda and cream of tartar.
More sensory play activities to try
Check out our other sensory activities for more fun.
I hope you had fun making our green Oobleck. If so, connect with us and share a comment or review below.
How To Make Oobleck Without Cornstarch?
- 1 cup Arrowroot Flour lighly packed in the cup, swept
- ⅓ cup Cold Water +2-3 tablespoons if needed
- 2-3 drops Food Coloring
- In a large bowl or plastic bin, add arrowroot flour, cold water, and food coloring.
- Stir with a spoon then by hand. You know you reach the right oobleck texture when it's hard when you apply pressure onto it, crumbly when you grab by hand but runs out like a liquid as soon as you open the hand and release the pressure.
- If it's too dry and impossible to gather by hand, add extra water 1 tablespoon at a time. If too liquid and more arrowroot flour.
- You can store oobleck in plastic bags or airtight containers for a few days in the fridge. However, the smell turns bad with time, especially if stored at room temperature.
- Clean the oobleck with water. It dissolves very well. The hardest part to clean up is the food coloring.