corn starch and water experiment Archives

Making an experiment with oobleck is very easy and a lot of fun for kids (and adults too!). The name oobleck comes from a Dr. Seuss story and is used commonly nowadays to name a non-newtonian fluid made from cornstarch and water. A non-newtonian fluid is a fluid that does not behave according to Newton’s law of viscosity. In other words, it has a different resistance to flow. It is sensitive to pressure and will change from solid to liquid depending on how much pressure we put on it. Because it is so easy to make at home, and it behaves so differently from other things we know, it creates the perfect environment for sneaking in some STEM learning.

In our house, we love to add color to anything. So when we decided to make some oobleck the other day, we got out our food coloring and added it to the mix. The result was fascinating! Because of the special properties of the mixture the colors created beautiful curves and spirals before mixing. In this post, you will learn how to create rainbow art and more brilliant ways to experiment with oobleck. You will also find out how you can engage with your kids so that they can learn from this experiment.

Oobleck Recipe

All you need to make oobleck is cornstarch, water, and food coloring. We made it in a large oven tray so that we could spread it out before adding color. This way you will get the beautiful effects I was talking about earlier. You will usually need around twice the amount of cornstarch than water (2 cups of cornstarch to 1 cup of water). These would be the steps to follow:

In a large oven tray add 1 cup of water
Start adding cornstarch until you reach the desired effect (oobleck should feel hard when you try to make it into a ball but as soon as you stop it will flow through your fingers)
Once you achieve the right consistency let it settle and start experimenting

5 Brilliant ways to experiment with oobleck for STEM learning

Making Oobleck in itself is already an awesome and fun experiment. However, the experiment doesn’t have to end there! If we want learning to stick, we have to go beyond the initial experiment and allow our children to do some discovery on their own. Here are some suggestions for keeping them engaged and curious about the experiment:

Add drops of color and make some rainbow art. This was our favorite part! Yes… adults enjoy this too!
Play with loose parts. We used colorful tops and our kid made towers using the oobleck as glue!! Just collect some objects and leave them around the experiment area and see what your kids come up with
Use kitchen utensils and observe how different this mixture is to manipulate compared to water
Create droplets outside of the tray. We did this outside on our waterproof tablecloth we use for experiments so we didn’t mind the mess. We let some drops fall out of the tray and observed what happened when they dried out. We compared bigger drops and smaller drops and then we added them back to the tray for more fun effects
Make a ramp and let the oobleck flow down. We just put a block under our tablecloth, no fancy ramp needed for this but feel free to make one too. We talked about rivers and lakes with this and how different liquids flow

Check out how our rainbow art turned out in this video:

Experiment with Oobleck observations and conversations

If you are doing this with preschool-aged children it is great to just talk and make observations while you do the experiment. By talking with your kids you are helping them build vocabulary so that they can understand the world better. When we make observations, we help them reflect on what is happening and connect ideas. So here are some suggestions when making the oobleck:

Add cornstarch gradually and observe the changes: is it getting harder?
Try to make little balls with your hands: what happens? As soon as you stop trying to roll the oobleck into a ball it will flow across your hand
What happens if you poke the oobleck fast? What happens if you just gently put your finger on it? When poking fast the oobleck should behave more like playdough being poked and when going slow it will behave more like pancake batter

For older elementary school kids you can add complexity to your conversation by talking about the following concepts and asking questions:

Liquid/solid: when does it behave like a liquid/solid?
Viscosity: how does this mixture flow compared to water? You can use a ramp to compare
Pressure/force: when we apply pressure what happens? Does the amount of pressure change the consistency?
Color mixing: what happens when we add drops of color? Why do you think it doesn’t mix directly?

We always suggest to wonder out loud with your kids instead of asking question after question. For example, “if I apply pressure I wonder what will happen?” or “what do you think will happen when we add color?”. It is always more fun to discover together than to be drilled.

Follow-up activity: Comparisons

Once you’ve explored oobleck, make something else. We mixed plain wheat flour with water to see how different the results were. It’s good for kids to have something to compare and as a bonus the entertainment lasted even longer!

This is definitely something you can repeat many times and it is always fun. And each time you do it you might find some cool way to play and experiment with oobleck. So make sure to always have cornstarch and food coloring available.

Happy STEM learning!

Check out other brilliant activities for young kids: