Wondering how to make oobleck? Our oobleck recipe is the perfect way to explore science and a fun sensory activity all in one!  Just two ingredients, cornstarch and water, and the right oobleck ratio make for tons of fun oobleck play. Oobleck is a classic science experiment that demonstrates a non-newtonian fluid perfectly! Is it a liquid or a solid? Use our oobleck recipe to decide for yourself and learn more about the science behind this goopy substance!


How to make oobleck recipe

What Is Oobleck?

Oobleck is an excellent example of a mixture!  A mixture is a material of two or more substances combined to form a new material that can be separated again. It’s also a very messy sensory play activity. Combine science and sensory play in one inexpensive activity.

The ingredients for oobleck are cornstarch and water. Would your oobleck mixture be separated into cornstarch and water again?  How?

Try leaving a tray of oobleck out for a few days.  What happens to the oobleck?  Where do you think the water has gone?

Plus, it’s non-toxic, just in case your little scientist tries to taste it! You can also combine oobleck with fun seasonal and holiday themes! Once you know how to make oobleck, you can try many fun variations. Why not…

Make rainbow oobleck in different colors.

Create a treasure hunt oobleck for St Patrick’s Day.

Add some candy hearts to a Valentine’s Day oobleck.

Or try red hots in your oobleck for a fun swirl of color.

Earth Day oobleck is a beautiful swirl of blue and green.

Make applesauce oobleck for Fall.

Did you know you can make oobleck in a pumpkin?

What about a spooky Halloween oobleck recipe?

Or try cranberry oobleck for a STEMs-Giving!

Add peppermints for a Christmas-themed oobleck recipe.

Make a melting snowman for a winter theme oobleck recipe.


Oobleck is a fantastic, fun, simple, and quick science lesson for kids of all ages. Even your youngest scientist will be amazed by it. What state of matter is oobleck? Here we combine a liquid and a solid, but the mixture doesn’t become one or the other. 

A solid has its own shape, whereas a liquid will take the shape of the container it is put into.  Oobleck is a bit of both! Learn more about states of matter here.


That’s why oobleck is called a non-Newtonian fluid.  This means it is neither a liquid nor a solid but has properties of both!  A non-newtonian fluid demonstrates variable viscosity meaning that the viscosity or thickness of the material changes when force is applied (or not applied) to it. Homemade slime is another example of this type of fluid.

You can pick up a clump of the substance like a solid and then watch it ooze back into the bowl like a liquid.  Touch the surface lightly, and it will feel firm and solid. If you apply more pressure,  your fingers will sink into it like a liquid.

Also check out our Electroactive Oobleck… It’s electric!

Is oobleck a solid?

A solid does not need a container to keep its shape like a rock.

Oobleck being shown as a solid

Or is oobleck a liquid?

A liquid takes the shape of any container or flows freely if not put in a container.

Oobleck being shown as a liquid

Did you know that cornstarch is a polymer? Polymers have long chains that make them up (like the glue used in slime). When these chains get all tangled up with one another, they create more of a solid! That’s why cornstarch is often used as a thickener in recipes.

If you enjoy making oobleck, why not try making slime with our favorite slime recipes! Slime is another fantastic way to explore states of matter, chemistry, and non-Newtonian fluids!

If simple science experiments are your thing, then our Science Challenge Calendar below 👇 is a fantastic way to keep track of what you have tried and make a plan to try a new science project.

Grab this FREE Jr. Scientist Challenge Calendar with Clickable Links!


This simple recipe is a hit to make over and over again. Make sure to watch the video. If you love our activities, find all the printable recipes in the Little Bins Club!

Oobleck Ingredients:

  • 2 cups cornstarch or corn flour
  • 1 cup water
  • Food Coloring (optional)
  • Small Plastic Figurines or Items (optional)
  • Baking Dish, Spoon
  • Book Optional: Bartholomew and the Oobleck by Dr. Seuss


Oobleck is a combination of two cups of corn starch and one cup of water. You will want to keep additional cornstarch on hand if you need to thicken the mixture. Generally, the oobleck recipe is a ratio of 1:2, so one cup of water and two cups of cornstarch.

Alternatively, you can make oobleck with another starchy flour, such as arrowroot flour or potato starch. However, you may need to adjust the ratio of flour to water. It’s a perfect science experiment for preschool through elementary school!

STEP 1:  In your bowl or baking dish, add the cornstarch. You will mix two parts cornstarch with one part water.

Note: Mixing the oobleck in a bowl and then transfering it to a baking dish or tray may be easier.

adding cornstarch to bowl on tray

STEP 2:  Add the water to the cornstarch. If you want to give your oobleck a color such as green, add food coloring to your water first. If you want to add swirls of food coloring after you mix the oobleck you can also do that, see marbled oobleck here.

NOTE: Remember that you have a lot of white cornstarch, so you will need a good amount of food coloring if you want a more vibrant color.

adding green water to cornstarch

STEP 3:  MIx! You can stir your oobleck with a spoon, but I guarantee you will need to get your hands in there at some point during the mixing process.

STORING OOBLECK: You can store your oobleck in an airtight container, but I would not use it for longer than a day or two and check for mold before using it. If it has dried out some, add a very tiny amount of water to rehydrate it, but just a very tiny bit. A little goes a long way!

DISPOSING OF OOBLECK: When you’re done enjoying your oobleck, the best option is to scrape most of the mixture into the trash. The thick substance may be too much for your sink drain to handle!

Using a spoon to mix cornstarch and water


There is a gray area for the right oobleck consistency. Generally, the ratio is 2 parts cornstarch to one part water. However, you don’t want it to be crumbly, but you also don’t want it too soupy.

The perfect oobleck recipe ratio is when you pick up a clump in your hand, form it into a ball of sorts, and then watch it flow back into the pan or bowl like a liquid. Luckily you can alter the consistency by adding a little more of one ingredient. Only add small amounts until you reach the desired texture.

If you have a reluctant kiddo, hand them a spoon to start. Let them warm up to the idea of this squishy substance. A potato masher is fun too. Even poking with one finger or pushing in small toys is a great way to start. You can also keep a wet papertowel to wash with nearby.

Once your oobleck is mixed to the desired consistency, you can add accessories and play like plastic animals, LEGO figs, and anything else that can be easily washed!

Plastic figures being drizzled with oobleck for Bartholomew and the Oobleck


You can turn this oobleck recipe into a fun oobleck experiment. Oobleck is an easy science fair project!

How? Change the ratio of water to cornstarch, and you have a viscosity experiment. Viscosity is the physical property of fluids and how thick or thin they are, including how they flow.

What happens when you add more cornstarch?  Does the oobleck become thicker or thinner? What happens when you add more water?  Does it flow faster or slower?

Can You Make Oobleck Without Cornstarch?

You could even try an oobleck recipe with flour, powder, or baking soda instead of cornstarch. Compare the similarities and differences. As mentioned in the ingredients section, look for arrowroot flour and potato starch. Do the same quantities work? Does the substance have the same characteristics as the original oobleck recipe?

We tried an oobleck experiment of our own using cornstarch and glue. Find out what happened —> Oobleck Slime

Have you ever mixed cornstarch and shaving cream for Foam Dough? It’s delightfully soft and smooth.

Cornstarch and Shaving Cream


If your preschooler through middle schooler is looking for more simple science activities at home, this home science experiment list is a great place to start!


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