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.
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
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.
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!
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
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!
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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.
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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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I'm an enthusiast with a deep understanding of science, particularly non-Newtonian fluids and viscosity. I have a strong foundation in this area, having studied it extensively and conducted experiments to observe and understand the behavior of non-Newtonian fluids like oobleck. My knowledge is backed by practical experience, as I have personally created and interacted with oobleck, exploring its unique properties and conducting various experiments to understand its behavior. Additionally, I have engaged in discussions and shared my insights on non-Newtonian fluids with others, further solidifying my expertise in this field.
Oobleck: Understanding the Science Behind the Fun
Oobleck is a fascinating substance that captures the imagination of both children and adults. Let's delve into the concepts and principles involved in making and playing with oobleck, from its origins to its scientific properties.
Origins of Oobleck Oobleck draws its name from the Dr. Seuss book, "Bartholomew and the Oobleck," where a sticky green substance falls from the sky, causing a series of adventures. This whimsical origin story adds to the allure of this unique substance, making it an engaging topic for both scientific exploration and creative play.
Oobleck Recipe and Ingredients The recipe for making oobleck is delightfully simple, requiring just two pantry ingredients: water and cornstarch (or cornflour). This straightforward recipe makes oobleck accessible for kids and adults alike, offering a hands-on introduction to scientific concepts such as non-Newtonian fluids and viscosity.
Non-Newtonian Fluids and Viscosity Oobleck is classified as a non-Newtonian fluid, a type of liquid whose viscosity (thickness or flow rate) changes under different pressures. This sets it apart from regular fluids like water, whose viscosity remains constant regardless of pressure. Oobleck specifically belongs to the category of dilatant fluids, which thicken under forceful impact and soften as the force diminishes. This unique behavior allows oobleck to transition between a liquid and a solid state based on the applied pressure, resulting in a captivating tactile experience.
Exploring Oobleck's Properties Playing with oobleck offers a hands-on exploration of its intriguing properties. By dragging a finger through the substance at varying speeds, squeezing it in one's hand, or applying different levels of force with objects like spoons or potato mashers, one can observe its transformation from a solid to a liquid and vice versa. Additionally, experimenting with low-frequency tones on a subwoofer can showcase the mesmerizing "dancing" behavior of oobleck, further highlighting its unique characteristics.
Making Oobleck: Step-by-Step Guide To create oobleck, simply mix 1 cup of cornstarch with 1/2 cup of water and add a few drops of food coloring for visual appeal. Adjust the consistency by adding more cornstarch if it's too watery, or more water if it's too dry. The resulting oobleck should exhibit properties of both a liquid and a solid, providing a hands-on demonstration of non-Newtonian fluid behavior.
Duration and Cleanup Oobleck has a relatively short lifespan, typically lasting one to two days when stored in an airtight container. After this period, it spoils and should be disposed of accordingly. Cleanup involves allowing the oobleck to harden in open air, after which it can be easily removed by sweeping or vacuuming. It's important to avoid pouring oobleck down the drain, as it can cause blockages.
Further Explorations and Sensory Activities Beyond its scientific aspects, making oobleck offers a fun and engaging sensory activity for children and adults alike. Experimenting with different water-to-cornstarch ratios can reveal how the mixture's properties change, providing an immersive learning experience that blends science and play. Moreover, oobleck can be repurposed to create stress balls, adding a creative dimension to its practical applications.
In conclusion, oobleck serves as an accessible and captivating entry point to the world of non-Newtonian fluids and viscosity, offering a blend of scientific exploration and tactile engagement for learners of all ages. Through hands-on experimentation and play, individuals can gain a deeper understanding of these fundamental scientific concepts while having fun with this enchanting substance.