Oobleck is a fascinating concoction created by mixing two readily available ingredients found in most kitchen cupboards: cornstarch and water. And, if you’re feeling a bit more creative, you can even add a dash of food colouring to give it some pizazz.
For instance, when we were making ours, we went with a spooky shade of green to transform it into a make-believe witch’s brew, perfect for the Halloween season. However, you have the freedom to leave it in its natural hue or tint it with any colour of your choice.
What makes Oobleck truly captivating is its simplicity. This easy-peasy recipe is not only a breeze to whip up but also a delightful sensory experience for kids.
What is Oobleck?
Oobleck isn’t your typical liquid or solid; it’s what scientists call a non-Newtonian fluid. This means it behaves in a rather intriguing way. Sometimes, it appears solid, and at other times, it acts like a liquid, but it doesn’t conform to the usual behaviour of solids or liquids.
Making Oobleck serves as a fantastic science experiment that demonstrates how altering pressure can transform the characteristics of certain materials. Think of it as how temperature can change the properties of water. When it’s cold, water becomes solid ice, while warmth melts the ice back into a liquid state.
Now, let’s see how you can observe the impact of pressure on your oobleck. If you apply sudden pressure with a spoon, you’re essentially pushing the cornflour particles closer together, which increases Oobleck’s viscosity.
As a result, it will feel rigid, and you might even be able to shape it into a ball using your hands. On the other hand, when you release the pressure or gently immerse your spoon into the mixture, the oobleck will act more like a liquid.
This happens because, with the slower movement, the cornflour particles have sufficient time to move out of the way, allowing the substance to flow more freely. It’s a fascinating way to demonstrate the unique behaviour of Oobleck when subjected to varying degrees of pressure.
Here’s a simple list of what you’ll need to create your Oobleck:
2 cups of cornflour
1 cup of water
Food colouring (if you want to add some colour)
Note: You might also see cornstarch referred to as cornflour, but it should be the white variety you use.
How long Does Oobleck last?
Now, let’s talk about how long Oobleck lasts. Oobleck stays good for about a day. After that, it starts to change.
When it’s time to get rid of your oobleck, we prefer to let it dry out overnight. The next day, you can easily break it into small pieces with a spoon, which can then be thrown into your green bin for disposal.
If you’d rather wash it away, just remember to mix it with a lot of hot water to ensure it goes down the drain smoothly.
How to make
Here are some simple steps and tips for making and handling Oobleck:
- Start by pouring the cornflour into a bowl, then gradually stir in the water.
- If the mixture seems too dry, add a few drops of water.
- If it’s too runny, sprinkle in more corn flour. The ideal Oobleck consistency is when it’s thick yet fluid, and it begins to tear apart if you stir it vigorously.
- Oobleck can become drier as you play with it. If that happens, just add a few drops of water to soften it up.
Helpful Hints for Oobleck-Making
- Oobleck can get quite messy, so it’s a good idea to either play with it outdoors or in an easily cleanable area like the kitchen. Roll up your sleeves and consider wearing aprons for added protection.
- If you want to give your Oobleck some colour, add a few drops of food colouring to the water before mixing it with the cornflour. Trying to mix it in later can be quite tricky.
- If your Oobleck doesn’t achieve the desired solidity, stir in ½ teaspoon of cornflour at a time until it reaches the consistency you prefer.
- Oobleck maintains its playability for a couple of days. Just add a small amount of water to reinvigorate it. Keep in mind that it can pick up lint and dirt, so it’s not recommended to use it beyond this time or play with it if it becomes dirty.
- For cleanup, you can use a piece of oobleck to easily gather up smaller puddles or clumps. Wipe your hands and any equipment with kitchen paper, and rinse under clean water.
- A damp cloth is effective for cleaning any surface. To dispose of Oobleck, leave it uncovered on the countertop overnight, and then scrape the dried mixture into the bin.
How to store
- Put it in a sealed container, like a plastic box or bag.
- Remove as much air as possible from the container to keep it from drying out.
- Store it in a cool, dry place away from sunlight and extreme temperatures.
- If it dries out, add a little water, seal it, and knead it to bring it back to the right consistency.
- Check it from time to time, and if it can’t be fixed with water, make a fresh batch.
That’s all there is to oobleck-making.