Oobleck combines cornstarch and water to create a substance that can behave like both a solid and a liquid. We’ll show you how to make oobleck. This recipe is easy and entertaining to prepare. It’s much simpler than making slime, and children love experimenting with it!
RELATED: Fluffy Slime
Oobleck consists of cornstarch and water—two items you probably already keep in your kitchen cabinets! Food coloring can be added as well. We colored ours green and transformed it into a pretend Witch’s brew for Halloween. You can keep it plain or choose whatever color you prefer.
Children will enjoy touching and playing with this quick and simple recipe! If you’d also like to make slime, all of our slime recipes can be found here.
What Is Oobleck?
Oobleck is neither a liquid nor a solid; it is a non-Newtonian fluid. It can sometimes look like a solid or a liquid, although it behaves unlike an ordinary solid or liquid. Creating oobleck makes an excellent science experiment for demonstrating how changes in pressure can affect the characteristics of certain materials. This is somewhat similar to the way temperature alters water’s properties. Low or freezing temperatures transform water into ice, while warmer temperatures melt ice and return it to a liquid.
Here’s how applying pressure to your oobleck demonstrates the difference: Press down quickly with a spoon, and the oobleck’s viscosity will rise as the cornstarch particles are pushed together. It will feel firm, and with your hands you may even shape the oobleck into a ball. Ease off the pressure or slowly lower your spoon into the mixture, and it will behave more like water. When you move gradually, the cornstarch particles have enough time to shift aside.
To connect this activity with a story, you can read the Dr Seuss book, Bartholomew and the Oobleck.
Oobleck Ingredients
These are the ingredients required for this oobleck recipe:
Note: Cornstarch is sometimes called cornflour. Be certain that you use white cornflour.
How Long Does Oobleck Last?
Oobleck keeps for one day. Once that time has passed, it begins to spoil.
For disposal, we prefer to leave the oobleck out to dry overnight. The following day, break it into small pieces with a spoon and put them in your green bin. If you plan to rinse it away, combine it with plenty of hot water first.
Watch the Video Tutorial!
How to Make Oobleck: Step-by-Step Instructions
Follow these step-by-step directions to make oobleck:
1. Add 2 cups of cornstarch and 1 cup of water to a bowl.
Stir the cornstarch and water together until the oobleck comes together.
Tip: To give your oobleck some color, mix the food coloring into the water before combining it with the cornstarch.
Halloween Activity Suggestion: To create Witch’s brew oobleck, make this recipe repeatedly until your cauldron is filled. This 14 inch cauldron works wonderfully for this activity.
2. If the mixture seems overly watery and does not become solid when you lift the oobleck from the bowl, add additional cornstarch.
If the mixture does not flow like a liquid, stir in a small amount of water. Continue testing it until the texture matches the consistency shown in the video above.
Activity Suggestions:
- Use a potato masher or spoon to strike the surface of the oobleck quickly. You’ll see the spoon or utensil rebound, making the oobleck seem solid. As explained earlier, the pressure pushes the cornstarch particles together and increases the oobleck’s viscosity. Next, lower your spoon slowly into the oobleck so the particles have time to move aside, allowing the spoon to sink into the mixture.
- Gather the oobleck in your hands and shape it into a ball. Release it afterward and watch it flow through your hands as if by magic!
- Create a Halloween version! Place small spiders, eyes, and approximately 10 batches of oobleck, depending on the size of your cauldron, inside it. Color the mixture green or purple for a Witch’s brew effect!
Kids will have a wonderful time reaching into the witch’s brew to search for Halloween treasures while discovering the science behind it!
We’re sure your kids will enjoy creating this straightforward science experiment! It’s ideal for a Halloween celebration or a fun activity on a rainy day. Don’t forget to explore all of our slime recipes for more ways to investigate the science of slime!
More Science for Kids
- Fluffy slime is a fantastic project to try! Its texture differs from traditional slime, making it especially enjoyable to play with.