When our grocery order comes from AmazonFresh, there’s usually a couple chunks of dry ice in with the frozen items. That offers great opportunities for fun science play. We have played with regular ice too, teaching the difference between solid, liquid, and gas. Our first game with dry ice was a few days later, where I explained that dry ice goes straight from solid to gas. Yes, you can use the word “sublimate” if your toddler likes big words like mine does. That day, we just put the dry ice outside in the sun, and watched it steam. Then added water to accelerate the process.
The next game was just pouring water droplets onto the dry ice – it gathers into balls and rolls off. I’m sure someone else could explain the science of this….
And a close-up:
The next time, we added food color to our water. Made blue water droplets, which was fun. But even better – after we stopped playing, we flipped over the dry ice – the blue water had all frozen to the underside of the dry ice.
We wondered what happens when you put dry ice in a baby bottle… We put in dry ice and little water. It turns out the hole in the nipple releases some of the gas and lets a little water escape, but not enough – the pressure was building quickly and I was worried the nipple would break or fly off (never put dry ice in a completely closed container – it could explode!), so I unscrewed it, and discovered this sound effect… After a couple minutes of playing with it, my husband calls downstairs, saying “What is that noise??? Is it the dog??”
The next time, we put dry ice in a sippy cup with a straw. We added a little water, then screwed on the lid – As the vapor expands, it forces the water out the straw, making a great little geyser. Which was completely unexpected the first time (though I now realize I could have predicted it) but VERY funny!
But then, even better, add bubble solution or bubble bath to the water. (We liked the results better with bubble bath.) So, put the dry ice in. Pour in a little bubble bath. Pour in a little water, and seal the lid. You can see our fountain in the video at the top of this post…. followed by lots of bubbles.
Here’s what happens if you don’t screw the lid on all the way.
And when you leave the lid off and let your toddler play with bubbles while you clean the kitchen:
And the latest experiment? Dry ice, water, and bubbles in a sippy cup.
As we play, I talk about the solid ice turning into gas. And I talk about surface tension with the bubbles. I’m starting to give science vocabulary.
But, this isn’t about drilling in science ideas so in 15 years my kid can go to MIT. It’s about having fun together, and laughing, and experiencing science hands-on. Learning that the word “science” means FUN, discovery, experimentation, and observation.
So, where do you get dry ice? I hear you can get it at most grocery stores, ice cream shops, Walmarts… There are dry ice directories on line but I suspect those are for larger quantities. For home use, you only need a little. One 2 inch by 2 inch square can last for 15 – 20 minutes of bubble play. Learn more here about how to get it: http://www.wikihow.com/Buy-Dry-Ice
Safety note: It’s really important to explain to your toddler that they MUST NOT touch the dry ice, because it will “burn” their fingers!! It is -100 degrees Fahrenheit! Treat it with the same caution you would treat a hot frying pan. I use kitchen tongs to handle it and point out the importance of doing so.
Are you a parent of a 3 – 6 year old in the Seattle area? Come join our Family Inventors’ Lab! Are you a parent or educator anywhere who wants ideas for STEM enrichment for young children? Check out my blog: www.InventorsOfTomorrow.com.