Note: This post contains affiliate links. You may read my disclosure here.

My goal is to make our STEAM activities super easy to set up and execute, and most importantly, give kids the “wow” reaction by the end! This reaction is what will get them excited about STEAM and keep coming back for more experiments.

Today’s experiment perfectly hits those goals! With just a few common household supplies you’ll be ready to fascinate your kids and spark their love of science.

Start by watching us do this experiment in our latest YouTube video, then follow along with my step by step instructions below.

Safety:

This experiment involves fire. Please make sure your candle is stable on your plate by securing it to the plate with play dough or brain flakes (what we used) before lighting the candle. I highly recommend an adult light the candle and place the mason jar over the candle.

Please take these precautions seriously and keep your kids a safe distance away from the flame to prevent burns.

We tried to involve the baby in this activity, but she immediately tried to grab the candle, so we decided to keep her away from this experiment. I’d recommend this activity for kids ages 4+.

Good thing our candle wasn’t lit yet, because the baby went straight for it!

Materials

  • Plate
  • Candle
  • Play dough or Brain Flakes to hold your candle
  • Water
  • Mason jar
  • Lighter or matches
My kids and I are ready to go with all our materials set up

Procedure:

  1. Set up the candle in the center of the plate. Make sure the candle is stable on the plate by setting it in a mound of play dough or we used my kids Brain Flakes STEAM toy as a candle holder. The hole in the center of the Brain Flakes was just the right size to hold the candle and we staked three Flakes for stability.
Here you can see the 3 staked Brain Flakes used as a candle holder in the center of our plate
  1. Pour about 1-2cm depth of water into the plate. We added water to the just below the top of the Brain Flakes holding the candle.
  1. Adult: Carefully light the candle with a lighter or match
My kids desperately wanted to blow out the candle right away! 🙂
  1. Adult: Carefully place the mason jar over the lit candle, with the jar opening facing downward onto the water filled plate.

Everyone was a little nervous as I placed the mason jar over the candle. Take your time placing it down so you don’t tip the candle over right away (I speak from experience).

  1. Watch what happens! Surprisingly to my kids, the candle doesn’t burn out immediately.
Our candle stayed lit for about 5 seconds – until it ran out of oxygen

After the candle burns out keep watching – the water will start to rise in the mason jar!

The air pressure in the jar is lower than outside the jar, and this differential draws the water into the jar

STEAM Concepts Learned:

Fire needs oxygen in order to keep burning as it converts it into carbon dioxide and water. When we covered the candle with the mason jar, the flame didn’t immediately go out because there was some oxygen inside the jar. When eventually all the oxygen was used up by the fire the flame went out.

Next, the water began to rise inside the jar. This happened because when the flame burned out the air inside the jar began to cool down and contract, which decreased the air pressure inside the jar. The outside air wanted to get to the area of lower pressure so it pushed water inside the jar until there was an equilibrium of pressure inside and outside the jar.

My kids and I really enjoyed this experiment. My kids were surprised by both how long the candle remained lit after we placed the mason jar over it, and also by the water rising in the jar after the flame went out! It was fun to watch their amazement with this easy STEAM activity!

Are you going to try this experiment at home? What do you think of our YouTube videos? Are they a helpful addition to the blog posts?

Disclosure

Some of the links below are affiliate links, which means that if you click on a product link I may receive compensation at no additional cost to you. I only link to products and pages I personally use and highly recommend. As an Amazon Associate I earn from qualifying purchases. Thank you for your support!

You have Successfully Subscribed!