Did you know you can make a miniature blizzard right in your own kitchen? Check out this cool science experiment that lets kids create a snowstorm in a jar!

This year is our first officially homeschooling our 2nd grader. After a year and a half of remote learning, we decided to just go for it and homeschool!

Although I was nervous at first, I have to say that it was the best decision we could have made. We all are LOVING it!

One thing I like about homeschooling is that we have the ability to do lots of fun hands-on stem-related activities anytime we want.

How to Make a Snow Storm in a Jar

This week we decided to try a classic winter themed kids science experiment: the blizzard in a jar. We don’t often get snow in Texas, so this is a way to have a bit of winter fun! It is also the perfect snow day science experiment for those of you who DO get real blizzards!

This is an easy STEM activity that uses only simple materials. Most of these are household ingredients or craft supplies that you might already have on hand! Even if you have to go out and buy all the supplies, you can probably find everything at the dollar store for $10 or less.

The verdict: snow storm in a jar is one of the best winter stem activities we’ve tried so far! It’s easy, low-prep, low-mess, and a visual way to learn about winter weather!

Supplies Needed

Quart Mason Jar — You can use a bigger or smaller jar, just keep in mind that you’ll need to adjust the ingredient amounts to match the size of your container.
Water — You’ll need 1-2 cups. Exact measurement isn’t necessary here, but you’ll just want to make sure that it’s not more than half the jar so you can see more “snow” swirling. The amount of water used should be LESS than the amount of oil used.
Baby Oil — A clear oil works best, so you can really see the color of the blizzard. We chose baby oil because it is clear and pretty cheap and easy to find.
Acrylic Craft Paint — Be sure that you’re using acrylic (water-based) paint, as opposed to oil-based paint. An oil-based paint won’t mix with the water and instead with try to mix with the oil. You’ll only need a small squirt of white paint (or blue paint, or any color you decide to use). No exact measurements needed!
Alka-Seltzer Tablets — You can use 1-2 at time. Generic is fine too, as long as it has the same active ingredients (sodium bicarbonate).

Instructions

In a separate bowl (not your mason jar), add a few drops of acrylic craft paint to no more than 1-2 cups of water. You don’t have to worry about exact measurements: you simply want less than half of the jar to be filled with this colored water.
Stir to blend water and paint. You can add more paint if needed. We used aqua paint for winter vibes (and because it is like the color of the sky), but you can use any color! White paint would be great too!
Fill your mason jar at least half way full with baby oil.
Slowly pour the water and paint mixture into your jar of baby oil. As you pour, you’ll notice that the paint mixture passes through the oil and settles on the bottom of the jar. Allow everything to settle completely before you start the experiment.

Optional: Mix in some glitter to the oil before you add the paint/water mixture to the jar. This makes it look even more like snow crystals! We did our experiment without glitter, so you can see what it looks like in our photos. Either way it’s lots of fun to make and watch!

When your jar is ready, your child can drop an Alka-Seltzer tablet inside and the snow storm begins!

We started with one tablet, so we could see the individual bubbles very clearly at first.

Then we added a second tablet and the storm got wild! So many bubbles!

I wouldn’t add more than 2 tablets at a time, as the mixture could foam over the top of the jar. And as long as everything stays in the jar, this is a mess-free activity!

The Science Behind the Snowstorm

This is a fun sensory experience — is is mesmerizing to watch the bubbles go up and fall back down. It reminds me of a lava lamp! However, there is some science involved here too!

1. Immiscible Liquids

Liquids that do not mix to create a single homogenous mixture are said to be “immiscible.” Oil and water are perhaps the most well-known examples of this phenomenon.

Water molecules are polar molecules, which means that one end has a positive charge and the other end has a negative charge (like a battery). The negative end of one water molecule will be attracted to the positive end of another water molecule. However, oil molecules are non-polar, so it will stick to itself and will never be attracted to a polar molecule like water.

When you try to mix oil and water, the water molecules will attract each other and bond tightly together. These secure bonds are more dense, since they are tightly packed. That’s why water sinks past the oil right to the bottom of the jar.

2. Pressure

Real-life storms, whether it be thunderstorms, hurricanes, or blizzards, are all the result of pressure changes in Earth’s atmosphere. Areas of low pressure draw winds towards them, air rises up and creates clouds and the condensation to create a storm.

Our snowstorm in a jar recreates this concept on a small scale. The Alka-Seltzer tablet creates a pressure change in our jar. The sodium bicarbonate in each tablet mixes with water and forms carbon dioxide gas, which pushes droplets of water up through the oil to the top of the jar. Then the water falls back down to the bottom, like snow flurries.

Can You Repeat the Experiment?

One thing I love about this activity (and what makes it unique from many other kids science experiments) is that you can do it again and again with the same jar.

Once your snowstorm has settled down, you can stir things back up again by adding another Alka-Seltzer tablet!

If you’d like to save it for later, allow ALL of the fizz to leave the jar. Then you can put a lid on it. Leave the lid loose at first to make sure there is absolutely NO air escaping still — you don’t want pressure to build up and break the jar.

More Winter STEM Activities