5 little pumpkins sitting on a gate; except These five little pumpkins are a pumpkin crystal science experiment. What a fun fall or Halloween science activity to pair with a classic book. Growing crystals with kids is easy to do and is a great chemistry activity for kids. Combine classic science experiments with fun themes kids love!

Easy to set up pumpkin crystal science experiment growing borax crystals with kids! Pair this pumpkin themed science activity with a classic book like 5 lLittle Pumpkins Sitting On A Gate! Growing crystals is awesome kid science you can do at home or in the classroom. Fall science, pumpkin science, crystal growing science for preschool, kindergarten, and early elementary age kids.

Explore Pumpkins For Fall Science

So what happens when 5 little pumpkins sit on a gate? They turn into crystal pumpkins! We enjoyed this pumpkin book and STEM challenge with real pumpkins, check it out here. This year, a pipe cleaner pumpkin crystal science experiment was in order!

Twisting your pipe cleaners into the shape of pumpkins for a fun way to grow crystal pumpkins. Abstract pumpkins if you will.

Growing crystals is a fun science activity that you can also turn into a science experiment. We will show you how to do that below! Let’s get started. Make sure to grab a copy of this classic book for the younger kids!

Using the Scientific Method

The scientific method is a process or method of research. A problem is identified, information about the problem is gathered, a hypothesis or question is formulated from the information, and the hypothesis is tested with an experiment to prove or disprove its validity.

Sounds heavy… What in the world does that mean?!? It means you don’t need to try and solve the world’s biggest science questions! The scientific method is all about studying and learning things right around you.

As children develop practices that involve creating, gathering data, evaluating, analyzing, and communicating, they can apply these critical thinking skills to any situation.

Learn more about:

More Helpful Science Resources

Here are a few resources that will help you introduce science more effectively to your kiddos or students and feel confident yourself when presenting materials. You’ll find helpful free printables throughout.

Get your FREE printable Pumpkin Science Activities

How To Make Crystal Pumpkins


  • Orange Pipe Cleaners
  • Green/Brown Pipe Cleaners
  • Borax Powder
  • Water
  • Glass Jars {Wide Mouth Mason Jars Work Best}
  • Measuring Spoons and Cups
  • Skewers or Pencils
Pumpkin crystal science experiment growing crystals with borax powder and pipe cleaners


STEP 1. Start out by twisting the orange pipe cleaners into pumpkin shapes.

We used one whole pipe cleaner per pumpkin. You can squish them around a bit to be longer or rounder as you please. Each one will definitely be unique!

TIP: Add a long green pipe cleaner stem which also serves as a way to suspend the pumpkins in the solution. You could also do brown and add leaves or make a curly vine!

STEP 2. Wrap the stems around a skewer or pencil. You don’t want the pumpkins to touch the sides or bottom as they will be difficult to remove. You could also use string if you find you need to lower them farther down into the solution.

STEP 3. Mix up your borax solution. See below! This is where the science comes into the activity because you have the opportunity to learn about mixtures and saturated solutions!

STEP 4. Suspend your pumpkins in the solution and LET IT REST UNDISTURBED for 24 hours. But make sure to observe the changes you see taking place. Remove from the solution and let dry on a paper towel!

Mixing up borax solution for pumpkin crystal science experiment

How To Make Borax Solution

  1. The ratio of borax to water is 3 tablespoons to 1 cup, so you can determine how much you need. This experiment to make 5 crystal pumpkins required 4 cups and 12 tablespoons divided between the containers.
  2. You want hot water. I bring the water to just boiling!
  3. Measure the correct amount of water and stir in the correct amount of borax powder. It will not dissolve. It will be cloudy. This is what you want, a saturated solution. Optimal crystal growing conditions!

You can read more on crystal growing but lets start with the basics. What you made in the beginning of the project is called a saturated solution.

pipe cleaners suspended in borax crystal growing solution

How To Grow Crystals

The borax has been suspended throughout the solution and remains that way while the liquid is hot. A hot liquid will hold more borax than a cold liquid! The molecules in hot water are much farther away from each other than in cold water allowing the water to hold more of the borax solution.

As the solution cools, the molecules return closer to each other and the particles settle out of the saturated mixture. The settling particles form the crystals that you see. The impurities remain behind in the water and cube like crystals will form if the process of cooling is slow enough.

If the solution cools to quickly, irregular shaped crystals will form due to the impurities that got caught in the process.

Saturated Solutions with borax crystal growing activity and pumpkin crystal science experiment

Fun Ways To Experiment

Covered vs Uncovered

For this particular experiment we chose to cover one of the jars with tin foil to slow down the cooling process. We found a heavier amount of crystallization on that glass container than the uncovered one.

I think had we used a mason jar {which we usually us}, we would have had even better results! The opening on a mason jar is not as big as the opening on these 2 cup measurers.

We didn’t get an awesome shot of the differences between the two but they were noticeable, so I will pass the challenge along to you!

Plastic Container vs. Glass Container

You can see the difference with this experiment here.

Using a plastic cup versus the glass jar caused a difference in the formation of the crystals. As a result, the glass jar crystals are more heavy duty, larger, and cube shaped.

While the plastic cup crystals are smaller and more irregularly shaped. Much more fragile too. The plastic cup cooled off more quickly and crystal pipe cleaners contained more impurities than those in the glass jar.

Our pumpkin crystal science experiment doubles as a terrific pumpkin science craft the kids will find fascinating. Who doesn’t want to grow their own crystals?

Crystal Pumpkin Science Experiment for Fall STEM Activities

More Fun Pumpkin Science Activities To Try

You don’t need to celebrate Halloween to enjoy pumpkin science activities. Try one or all of the ideas below!

Explore More Fall Science

Click on the images below for more Fall theme science activities.

Printable Pumpkin STEM Pack

Perfect for K-2/3rd Grade and homeschool! Many activities can be modified for preschool and older kiddos as well. 

Pumpkin is a festive and classic theme for fall and this pack is perfect for exploring pumpkins with a non-Halloween theme! Includes science, STEM, engineering, early math, and art projects.

100+ pages of “totally doable” projects the kids will have a blast trying! Read more here.


  1. The pumpkin crystal experiment is amazing! Can’t wait to try it with my son… He’ll love it. Thanks for linking to our beaded pumpkin craft!

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