
This simple Ivory Soap microwave experiment is so easy to do. It’s great for kids in preschool and kindergarten because they can really get their hands into it and use their five senses to observe how the soap changes when it is heated up. They will have a ton of fun while learning a little bit of science!
Getting the Ivory Soap Microwave Experiment Ready
This experiment is about as easy as it gets to set up! We only had to gather two supplies:
- One bar of Ivory Soap (it must be Ivory brand, which I’ll explain later)
- Ivory Soap
I printed out a couple of copies of the free printable worksheet (available below) so the kids could keep track of their results. We took a few minutes to look at the bar of soap, smell it, feel it, and write our observations on the worksheet. I asked the kids what they think will happen if we microwave the bar of soap. They couldn’t believe we were planning to put soap in the microwave! They took a few minutes to laugh and write down their hypothesis.
We headed into the kitchen and set up a couple of bar stools in front of the microwave so the kids could watch the transformation of the soap as it happened.
Microwave Ivory Soap
We placed the bar of Ivory Soap onto a plate and placed it in the microwave. The kids got up onto the stools to watch. I set the microwave for 90 seconds.
Within just a few seconds the soap started to puff up and expand like a fluffy cloud! It was amazing to watch!
The kids couldn’t believe their eyes! They cheered and clapped and couldn’t wait to get their hands onto the soap in its puffy condition.
Once the soap stopped expanding we pulled it out of the microwave. It was very hot so I set it aside for a couple of minutes until it was cooled down. We used this time to fill in the rest of the science worksheet by drawing a picture of the soap after it was microwaved and writing a short explanation of what happened.
Once the soap cloud was cooled down I let the kids dig right in. They loved crumbling it between their fingers. It still smelled really good and fresh and made our entire kitchen smell so clean!
The Science Behind The Ivory Soap Microwave Experiment
When Ivory Soap is manufactured it has a lot of air whipped into it. This air gets trapped into the bar in little air pockets. When the soap is heated in the microwave the air in those little pockets expands, making the entire bar of soap puff up.
Even after being microwaved the soap is still good to use! You can take it into the shower and use it just like regular soap or you can use it in any of these fun and creative ways.
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Download Your Ivory Soap Recording Sheet Below!
Can you not find a resource that you would LOVE to have for your classroom? Contact me and I would be happy to make it for you.
Click the picture below to download.

I hope that you and your students enjoy the Ivory Soap Experiment to use in your classroom this year!
What do you do with the Ivory soap after it has cooled? Does it harden again, or does it stay pliable?
The soap turns into a crumbly powder, so you’d have to throw it out or add it to your laundry soap or something if you wanted to save it.
Add 2 tablespoons of water per bar of soap and mix until it feels like play dough. Add 3 drops of soap dye/coloring, mix… put cookie cutters on wax or parchment paper. Fill with soap dough, packing tightly. Air dry until it is hard…
I love love love science! Can’t wait to do this experiment with the kiddos! Who we fooling? I CAN’T WAIT MYSELF!
You are a very intelligent person!