We did these with our friends and we had so much fun! Just make sure that you use Ivory soap because it has air whipped into it so when it gets hot it expands. We tried dial soap just for fun and it grew a tiny bit. We put the dial soap and the ivory soap in a bowl of water and the ivory floated, the dial sank showing just how much air is in the ivory.
What You Need
– Wax Paper
-Ivory Soap
– Cookie Cutters
– Food coloring
Unwrap your soap and set it on the wax paper. 
Put it in the microwave for one to two min and watch it grow. Two minutes makes the cloud touch the sides of our microwave. Be careful the center can be hot right at first.
Make sure that wax paper is covering most of the bottom of the microwave so when it grows it does not get all over. When you are done, pull it out and wipe the inside of the microwave off so doesn’t smell like ivory.
Eventually it will start to crumble and start to get messy. That is when you can make it back into soap that you can use. 
Pour the crumbles into a bowl, add a little bit of water and food coloring and knead it with your hands. Cover a cookie sheet with wax paper to use as your work area. Set the cookie cutters on the cookie sheet and start filling the cookie cutters with your soap mixture. Don’t use cookie cutters that have a bar across the top because then they won’t come out very good. 
Let the soap dry in the cutters for a while until they are dry and pop them out of the cookie cutters and ENJOY!
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We did it for two minutes and it filled up the microwave. We tried dial soap and it was fun to see the difference. Dial soap expanded but did not fluff up like ivory. The bar of ivory soap floated in a bowl of water. Dial soap sinks to the bottom.
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We just tried this and the kids loved watching the soap grow in the microwave. We found that taking it out and pulling off the fluffy stuff after a minute or so and then microwaving the stuff in the middle that didn’t expand worked well for us, kinda like peeling off layers of a roasted marshmallow, in fact this reminded me of the Stay Puff Marshmallow monster from Ghostbusters, but that was way before your time :) (don’t watch the movie but perhaps just watch that clip of Marshmallow monster on You Tube :) Finally I would note that the center that doesn’t expand can be quite hot so use caution especially with 3 year olds that want to just grab the fluffiness! Thanks for a great summer project! Well done Groovyglue!.
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That’s cool how it fluffs!! Maybe sometime I can go over to your house and some crafty things with you!
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