by Debbie Chapman
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Learn how to make oobleck with this simple recipe of cornstarch and water! Oobleck is SO FUN to play with and it’s a great science experiment for kids involving non-Newtonian fluids and viscosity.
Oobleck Recipe
Have you ever heard of oobleck?! This substance gets its name from a Dr. Seuss book, Bartholomew and the Oobleck. In the book, Bartholomew has to rescue his kingdom from a sticky green substance that falls from the sky.
You can make oobleck with only 2 pantry ingredients: water and cornstarch (aka cornflour). It’s a simple science experiment that’s somewhat similar to slime, but it’s a LOT easier to make and to clean up.
Oobleck is a substance known as a non-Newtonian fluid (read more on that below!). Have fun playing with this unique mixture and watching it change from a liquid to a solid right in your hands.
Check out our How to Make Oobleck video tutorial:
*Note: Scroll down for the step-by-step photo tutorial.
Looking for fun slime recipes? Here’s a few of our favourites:
How to Make Fluffy Slime
Clear Slime
Cornstarch Slime
Classic Homemade Slime
Here’s what you’ll need:
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The full printable instructions are at the end of this post, but here’s a list of products on Target that are similar to the supplies we used:
What’s the science behind oobleck?
Oobleck is a non-Newtonian fluid, meaning it’s a liquid where the viscosity (the thickness, or how fast or slow it flows) changes depending on pressure. This is different from a regular fluid, like water, where the viscosity (or thickness) always stays the same.
Oobleck is an example of a dilatant fluid, which hardens when shear (stress/forceful impact) is applied, and softens as the force decreases. In other words, it becomes a solid when you press on it and a liquid when you let it flow on its own.
What can I do with oobleck?
Drag your finger through the oobleck at different speeds. Grab it with your hand and make a fist: feel it harden, and then flow back into the bowl as a liquid when you let it go.
Hit it with a potato masher at different speeds as well. What happens when you smack the surface versus placing it in gently? Do the same thing with a spoon.
You can even try placing the bowl of oobleck on a subwoofer and playing low frequency tones to make the oobleck “dance” around. (Full disclosure: we tried this on a speaker and couldn’t get the oobleck to move, but other people online seem to have had success!)
How to Make Oobleck
Learn how to make oobleck with this simple recipe! Mix water and cornstarch for a fun and easy science experiment and STEM activity for kids.
Materials:
- 1 cup Cornstarch
- 1/2 cup Water
- 5 drops Food colouring
Instructions:
Add 5 drops of food colouring to 1/2 cup water.
Stir the water and food colouring together.
Add the coloured water to 1 cup of cornstarch.
Mix the cornstarch and water together with a spoon.
If the mixture is too dry and difficult to stir, add a bit more water.
Stir the mixture until it has a consistent colour and smooth texture. It should be easy to stir when you get moving, but will feel difficult and stiff when you stop moving.
Your oobleck is complete!
Helpful Tip:
If your oobleck is too watery and not forming a solid when you squeeze it in your hand, add more cornstarch, 1 teaspoon at a time.
If your oobleck doesn't "melt" into a stream of liquid when you let it go, you need to add more water - again, add it 1 teaspoon at a time.
How long does oobleck last?
Oobleck only lasts for 1 day, 2 maximum if placed in an airtight container (you can add a bit of water to refresh it). After that it will spoil and should be thrown away.
How can I clean up the oobleck?
Leave the oobleck out in open air and it will harden overnight. Then you can compost it or throw it in the garbage. (We don’t recommend pouring it down the drain.)
Leave any mess to dry up, if possible, and it can easily be swept or vacuumed up.
Try adding different amounts of water to the oobleck to see how the mixture changes. Learning how to make oobleck is part science experiment and part slime recipe – making it is such a fun sensory activity!
And did you know that you can make a stress ball with oobleck?! Check out the instructions for our oobleck stress ball!
Here’s even more fun slime recipes:
How to Make Fluffy Slime
Clear Slime
Cornstarch Slime
Classic Homemade Slime
Our bookLow-Mess Crafts for Kids is loaded with 72 fun and simple craft ideas for kids! The projects are fun, easy and most importantly low-mess, so the clean up is simple!
Where to buy:
You can purchase Low-Mess Crafts for Kids from Amazon, or wherever books are sold:
Amazon |Barnes and Noble | Books- A- Million | Indiebound |Indigo |Amazon Canada
More from One Little Project
About Debbie Chapman, the Author of this Post
I'm Debbie Chapman, founder of One Little Project and author of the book Low-Mess Crafts for Kids. I love creating fun and easy crafts and cooking up delicious recipes for my husband and 3 kids.
More by Debbie Chapman
Filed Under: How to Make Slime, Just for Kids, Kids Crafts and Activities, Preschooler and Toddler Activities, Science ExperimentsTagged With: cornstarch, food colouring, oobleck, science experiments, slime, STEM
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Insights, advice, suggestions, feedback and comments from experts
As an expert and enthusiast, I have personal experiences or the ability to engage in activities like making oobleck. However, I can provide you with detailed information about the concepts and instructions mentioned in the article.
Oobleck: A Non-Newtonian Fluid
Oobleck is a substance that falls under the category of non-Newtonian fluids. Non-Newtonian fluids are liquids whose viscosity (thickness or flow rate) changes depending on the pressure or force applied to them. Oobleck is a specific type of non-Newtonian fluid known as a dilatant fluid. It behaves differently from regular fluids, such as water, which have a constant viscosity.
When pressure or force is applied to oobleck, it hardens and behaves like a solid. However, when the force is removed and the oobleck is left undisturbed, it flows and behaves like a liquid. This unique property makes oobleck an interesting substance to play with and study, especially for children.
Oobleck Recipe and Instructions
To make oobleck, you only need two pantry ingredients: water and cornstarch (or cornflour, depending on your location). Here are the step-by-step instructions:
Materials:
- 1 cup of cornstarch
- 1/2 cup of water
- 5 drops of food coloring (optional)
Instructions:
- In a bowl, add 5 drops of food coloring to 1/2 cup of water. Stir the water and food coloring together.
- Add the colored water to 1 cup of cornstarch.
- Mix the cornstarch and water together with a spoon until you achieve a consistent color and smooth texture. The mixture should be easy to stir when in motion but will feel difficult and stiff when at rest.
- If the mixture is too dry and difficult to stir, add a bit more water. If it's too watery and doesn't form a solid when squeezed, add more cornstarch (1 teaspoon at a time).
- Your oobleck is complete and ready to play with!
Exploring Oobleck
Once you've made your oobleck, you can explore its unique properties. Here are some activities you can try:
- Drag your finger through the oobleck at different speeds. Observe how it behaves and feels.
- Grab a handful of oobleck and make a fist. Feel how it hardens when you apply pressure and then flows back into the bowl as a liquid when you release it.
- Hit the surface of the oobleck with a potato masher or a spoon at different speeds. Notice the differences in its behavior depending on the force applied.
- For a fun experiment, place the bowl of oobleck on a subwoofer and play low-frequency tones. Some people have reported that the oobleck "dances" around in response to the vibrations, although results may vary.
Cleanup and Shelf Life
Oobleck has a short shelf life and will last only for about 1 to 2 days. To extend its lifespan, you can store it in an airtight container and add a bit of water to refresh it. However, keep in mind that oobleck will eventually spoil and should be thrown away. When cleaning up oobleck, leave it out in the open air to harden overnight. Once hardened, it can be composted or thrown away. Avoid pouring it down the drain, as it can cause clogs.
Conclusion
Oobleck is a fascinating substance that provides an engaging and educational experience for kids. By making it and exploring its unique properties, children can learn about non-Newtonian fluids, viscosity, and scientific concepts related to materials and their behavior. The simple recipe and easy cleanup make it a convenient and enjoyable activity.
