Pumpkin Oobleck With A Real Pumpkin

Why make a Pumpkin oobleck? Because we love pumpkins! I have been so excited about all the awesome fall sensory activities we have tried this season. This non-Newtonian fluid is super fun when you add it to a pumpkin! Find new ways to learn and play with pumpkins this fall season.

What Is Oobleck?

Oobleck is a fun mixture to play with, which is made from cornstarch and water.   It’s a bit messy too!

It is an excellent example of a mixture!  A mixture is a material made up of two or more substances combined together to form a new material and that can be separated again.

Could the oobleck mixture be separated into corn starch and water again?  How?

Try leaving a tray of oobleck out for a few days.  What happens to the oobleck?  Where do you think the water has gone?

Oobleck Is A Non-Newtonian Fluid

This oobleck activity is also a great way to explore the properties of liquids and solids, known as the states of matter. Here, we combine a liquid and a solid, but the mixture doesn’t become one or the other.  A solid has its own shape, whereas a liquid will take the shape of the container it is put into.  Oobleck is a bit of both!

That’s why oobleck is called a non-Newtonian fluid.  This means it is neither a liquid nor a solid but has properties of both!  You can pick up a clump of the substance like a solid and then watch it ooze back into the bowl like a liquid.  Touch the surface lightly and it will feel firm and solid. If you apply more pressure,  your fingers will sink into it like a liquid.

Is oobleck a solid? Or is oobleck a liquid?

Did you know that cornstarch is a polymer? Polymers have long chains that make them up (like the glue used in slime). When these chains get all tangled up with one another, they create more of a solid!

Don’t miss out on making a Pumpkin-Cano! Watch the video too.

Free Pumpkin Project Guide and STEM Challenge Cards!

Pumpkin Oobleck 

Here’s how to make this super simple 3 ingredient hands-on science play with real pumpkins! I love checking out my kitchen pantry for supplies for science experiments. Our original how to make oobleck recipe is a hit all year round.

• Spidery Oobleck
• Peppermint Oobleck
• Candy Hearts Oobleck
• Apple Sauce Oobleck
• Cranberry Oobleck

YOU WILL NEED:

• cornstarch
• water
• pumpkin (we used half of a 3-pound sugar pumpkin from the grocery store)
• bowl and plate or cookie sheet and spoons

How To Make Pumpkin Oobleck

We only used half a pumpkin, which was perfect for our needs. Use the whole thing if you have a few kids or a class! However, we did bake the other half and made a delicious fall treat with it!

This mixture is for 1/2 a pumpkin. You might want to mix the oobleck in half when using the whole pumpkin. It’s a recipe you need to tweak to your liking and sensory needs.

STEP 1. Cut the pumpkin in half and loosen the guts and seeds (awesome time to discuss pumpkin parts too!) Set aside a few seeds to top the pumpkin afterward.

STEP 2. Measure 1 cup of cornstarch and pour into the pumpkin.

STEP 3. Add about a half cup of water to the pumpkin.

STEP 4. Mix well with hands! If the mixture feels too runny add a bit mmore cornstarch. Too dry? Add a bit more water. Just make sure to add very small amounts at a time!

STEP 5. Place the pumpkin on a cookie sheet or in a shallow tub for easy play.

Mixing Note: If the mixture is too runny, add more cornstarch and vice versa. You should be able to pick it up like a solid and have it begin to ooze as a liquid. That’s Oobleck in a nutshell! Also note, that you may need to adjust for the number of pumpkin guts in your pumpkin and the size!

Sensory Note: This can get oozy and gooey and provide quite a sensory punch. It’s not for everyone. My son enjoys using spoons but doesn’t necessarily care to get it all over his hands, so I don’t push it. He does enjoy oobleck because if you poke it with your finger, it feels firm and smooth with little residue.

Conduct An Oobleck Experiment 

Want to experiment with viscosity?  Easy, change the ratio of water to cornstarch!  Viscosity is the physical property of fluids and how thick or thin they are, including how they flow.

• What happens when you add more cornstarch?  Does the oobleck become thicker or thinner?
• What happens when you add more water?  Does it flow faster or slower?

YOU MAY ALSO LIKE: Applesauce Oobleck and Halloween Oobleck

Can you make oobleck without cornstarch?

You could try making oobleck with flour, powder, or baking soda and compare the similarities and differences.

We tried an oobleck experiment of our own using just cornstarch and glue.  Find out what happened —> Oobleck Slime

Check Out More Fun Pumpkin Activities 

• Pumpkin Volcano
• Pumpkin Slime
• Make A Pumpkin Clock
• Crystal Pumpkins
• Pumpkin Jack