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How to Make a Cloud in a Jar

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When it comes to teaching science experiments for kids, I have a hard time remembering to pick up supplies for the hands-on projects that make it fun.

That is why I love projects that can be made from supplies that you just have lying around the house (like this fun recipe for slime or these rainbow recipes for kids!)

We were curious how to make a cloud in a jar anyway! It’s the perfect addition to your spring STEM activities!

We found there are actually two fun ways to make a cloud in a jar.

One way to do it is to literally make your own cloud in a jar. The foggy cloud trapped in a jar is like magic for kids!

The second method illustrates how a rain cloud works. This water cycle experiment with shaving cream looks beautiful and kids love repeating this science experiment over and over again.

Want an easy way to teach kids how clouds form? This simple science experiment for kids on how to make a cloud in a jar is the perfect "wow" demonstration.

This experiment is found in our book The Mason Jar Scientist.

How Clouds Form for Kids

Curious about the science behind the cloud in a jar experiment? Here is the science behind each of the cloud science experiments.

And if you can’t get enough of weather science, try this fun puffy paint cloud activity!

Real Cloud in a Jar

make a cloud at home

Most kids are a little disappointed that clouds aren’t made of cotton candy or cloth-like they are often depicted in cartoons. You can’t sit on a cloud!

Clouds are made of cold water vapor that is condensed into droplets of water around dust particles.

Clouds are just fog high up in the sky.

You can make a cloud in a jar by placing ice on top of a jar filled with hot water. The sudden temperature change causes condensation to form.

Spraying the condensation with hair spray makes a cloud form!

Water Cycle Experiment with Shaving Cream

rain cloud in a cup

This lesson shows children how clouds form and why it rains. Water evaporating from the ground forms into clouds. When the clouds gets full of water, they release the water to the ground the make rain.

This version uses food coloring to visually illustrate the falling rain. Use the tutorial below to learn how to make a cloud in a jar.

Learn How to Make Clouds in a Jar!

Below you will find two differnet ways to make a cloud, one that makes a rain cloud and one that makes a real cloud!

spring stem challenges

Method 1: Cloud in a Cup

how to make a cloud in a jar

Make a real-life cloud in a jar using this tutorial!

What you need to make a cloud in a jar:

  • Hairspray
  • Jar with lid
  • Blue food coloring
  • Black paper
  • Small bowl
  • Ice

Cloud in a Jar Experiment Directions

Fill your jar about 1/4 of the way with water and dye it blue with food coloring.

Heat the water in the microwave for about 30 seconds (the hotter the better).

cloud in a jar

Be careful getting it out so you don’t burn any little hands.

Place your jar in front of some black paper. This makes it easier to see the cloud.

how to make a cloud in a jar

Spray a squirt of hairspray into the jar.

Put the lid on the jar.

cloud in a jar science experiment

Fill a small bowl with ice. Place the bowl on top of the jar.

Watch as the cloud forms in the jar.

Open the jar and release the cloud into the air!

how to make a cloud

If your cloud looks small, try heating the water more or placing the ice directly on the jar lid. You might also need to spray another squirt of hair spray in the jar.

Cloud in a Jar Science

cloud in a jar science experiment

Clouds form when condensation particles gather around air particles like dust or ice.

When you spray the inside of the jar with hairspray, it gives the condensation something to cling to.

Before the hairspray is added, the cloud is unformed and looks more like fog.

But after adding hairspray, a thick cloud forms!

The bigger the contrast between the top and bottom of the jar the more impressive the cloud.

Method 2: Rain Cloud Experiment

cloud in a cup

This is the easiest way to learn how to make a rain cloud in a jar.

Things you will need for your rain cloud in a jar:

If you’re in a rush, these are our favorite weather science kits.

Rain Cloud in a Cup Experiment Directions

Fill the glass mostly full with water.

Next, fill the top of the glass with white shaving cream. The more cream you add, the thicker your cloud will be, but the longer it will take for the food coloring to penetrate the cloud layer.

Have the child(ren) drip drops of food coloring into the “cloud” one at a time. It took longer for the cloud to rain than I thought it would, so be patient.

After a while, the drops will seep through the shaving cream and it will look like it is raining in the cup! Ours looked like a mini tornado.

After it stops “raining,” the food coloring will gradually disperse into every area of the cup, turning the water blue.

Rain Cloud in a Jar Science

rain cloud in a cup

The shaving cream cloud represents real clouds. When real clouds become too heavy with liquid, just like the food coloring became too heavy for the shaving cream to hold, they rain.

Talk about the cycle of weather and how the cloud in a cup is different from real clouds.

Discuss where water comes from, and why water evaporates.

Watch the cloud in a jar in action!

spring stem challenges

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