How to Make Oobleck

Did you know you can make Oobleck with only two ingredients? Sometimes it’s liquid, sometimes it’s solid, but it’s always fun to play with!

Whenever I need a quick activity to keep the kids entertained on a rainy day or when they are bored I grab cornstarch and water then mix up a batch of Oobleck.

The kids love playing with it because the texture changes depending on the force you apply to it. Plus, you can change the colors for the seasons or their moods!

What is Oobleck?

Is it a solid or a liquid? Actually it’s neither! Crazy, right? It’s called a non-Newtonian fluid. This means it may seem like a solid or act like a liquid, but is different then a normal liquid or solid. Confusing, right?

This science experiment shows how changes in pressure can change the properties of some materials.

To use this as a science experiment grab a spoon then apply quick pressure. This increases the viscosity in Oobleck forcing the cornstarch particles together and it makes it feel hard. With pressure you can even form it into a ball in your hands.

When you let the pressure off of the mixture it kind of melts and becomes a liquid again.

Oobleck comes from the Dr. Seuss book Bartholomew and the Oobleck where a gooey green substance fell from the sky, Oobleck, and wreaked havoc on the kingdom. Read the book and then make Oobleck for a fun activity in the classroom or at home!

Why You’ll Love This Activity

• This activity is an inexpensive way to keep kids busy and entertained.
• You only need 2 ingredients, and I know you’ve always got them on hand!
• This is a great hands-on science experiment for kids either in the classroom or at home.

What You Need To Make Oobleck

• Cornstarch – This can also be referred to as cornflour. I do not recommend using regular flour, you will not get the same consistency. Arrowroot flour, tapioca flour or potato starch are a good alternative.
• Water – Tap water is all you need.
• Paint or Food Coloring (optional) – We added a green tempera paint to ours, but you can use food coloring too!

How to Make Oobleck

Combine the cornstach and water in a bowl. Then mix until completely combined and no lumps remain.

If you want to color the it add a few drops of paint or food coloring to it and mix to combine.

Now, dig your hands in and play!

Pro Tips

• If the mixture is watery just add a little more cornstarch.
• If it is too thick add in a little water.
• Do not dispose of Oobleck in the sink. When you are done playing with it, throw it in the trash.

How long does Oobleck last?

It only lasts about a day before it separates and needs to be disposed of. It’s inexpensive and easy to make so once the kids are done playing just scrape it in the garbage or let it dry out overnight and scrape it out of the bowl the next day.

Ways to Play with It!

• Grab a handful, squeeze it to make it hard then release it to make it ooze out through your fingers.
• Drag your fingers through it in the bowl.
• Treat it like a sensory bin and add in things to see if they float or sink.
• At Halloween, add in eyes and spiders. You could even put it in a witch’s cauldron to make it festive.

Switch up the colors to make it festive and have fun making your homemade Oobleck!

More Activities for Kids!

• Everyone needs a go-to homemade playdough recipe and this one is hands down the best!
• Kids love doing science experiments and this one is even edible! Make your own homemade rock candy and enjoy it afterwards.
• Grab those empty toilet paper rolls, layer them with peanut butter and make Bird Feeders!
• This Butter Slime is so much fun to make and play with!
• Frozen Bubbles are another great science experiment to do with your kiddos.