What is Oobleck | Make Oobleck for kids

When I first read Dr. Seuss’ book Bartholomew and the Oobleck, I didn’t know I could actually make Oobleck. Once I made this Oobleck science project, I was really surprised to see that it is a liquid, and it is a solid too. When I tried to stir it fast, it was hard like a rock. but when I moved my hand slow, it was completely liquid and watery! How cool is that?

What is Oobleck

Oobleck is a non-Newtonian fluid, which means it is pressure dependent substance. If you apply pressure, such as tapping on the surface of Oobleck, it will increase it’s viscosity (thickness). Just try to pat it and you will see what I mean.

Many people call Oobleck a slime, goop, or goo. You probably know Oobleck from Dr. Seuss’ book Bartholomew and the Oobleck. Everyone wants to make a substance just like the one in the pictuers!

How to make Oobleck

For Oobleck science experiment you will need:


That’s it!

You can add food coloring, I added a couple drops of green food coloring to make it look like the Oobleck from Dr. Seuss book.

Mix two cups of cornstarch with one cup of water. If you are using food coloring, put a few drops into the water before you mix it with the corn starch.

Mix it slow. The faster you move, the harder it will be to mix it! Cornstarch dissolves pretty quickly and you will start noticing the amazing way Oobleck works. If you apply pressure to this mixture, such as pressure of your fingers when you try to stir Oobleck, the substance will act as a solid. That’s because pressure increases Oobleck’s viscosity by forcing cornstarch particles together. If you move slow, you give cornstarch particles more time to move and the substance acts more as a liquid.

We loved to play with the Oobleck. Take a spoon and tap the surface of the Oobleck. Watch how it becomes solid and you can tap it almost as if it was a rock.

What would you say? Is Oobleck a solid or a liquid?

Sign up to receive our easy-to-follow and fun lesson plans for your preschooler for FREE!

Oobleck recipes without cornstarch

There are many ways you can make Oobleck. Most of the time, it’s very easy two ingredient recipe that uses common household items.

Oobleck can be made from arrowroot flour, baby powder, or potato starch as well. Not every ingredient makes Oobleck feel the same though. Some ingredients make this non Newtonian fluid softer, and some harder. Baby powder makes it smell good as well!

Oobleck from Arrowroot flour

2/4 cups of arrowroot flour
2/3 cups of water

This Oobleck was very lumpy and kinda hard.

Oobleck from Baby Powder

2 cups baby of powder
1 cup of water

Find cornstarch based baby powder, not the talc based. I haven’t tried talc based powder so I don’t know if it would make good Oobleck. Let me know if you try it!

The smell of the baby powder can be very overwhelming when in large quantities (such as 2 cups of it!). Also, baby powder tends to be much more messy than cornstarch. The powder flies everywhere and you end up breathing it in. I’d just stick with cornstarch for making Oobleck.

Oobleck from Potato Starch

2 cups potato starch
1 cup water

This one is super soft and flowing nicely. We loved potato starch Oobleck and we will definitely make it again! Kids in my class thought this one was the best one!

How long does Oobleck last?

Depends on what you make it from! If you make cornstarch, or baby powder Oobleck, it kinda falls apart when it’s left to dry.

If you make Oobleck from potato starch, you can leave it out for a bit and still come back to play with it. But it won’t be Oobleck as we know it anymore! Once Oobleck from potato starch dries a bit, it’s more like a play-doh. You can mold it easier and it’ll hold it’s shape easier. I wouldn’t leave it out for too long though, only for a bit to dry a little bit of water out.
It’s actually really cool play-doh!

Is Oobleck edible?

Well, it’s taste safe. That means, nothing will happen to you if you lick a little bit. It’s doesn’t have any chemicals in it. But I wouldn’t eat it though. I don’t think it would taste good and I’m not sue if your or your child’s tummy won’t hurt with larger quantities of Oobleck are consumed.

Have you tried to make Oobleck? Did you like it? Which one did you make?

I’d love to hear your experiences and maybe even some tips and tricks!