Well, school’s out for winter break and we’re stuck indoors on a rainy day. What did we do? Science experiments of course!
Don’t be daunted when it comes to science and preschoolers. The goal is not to hammer home the scientific concepts, but rather to introduce tots to the strange, silly, and downright amazing things that happen when substances mix. I love this experiment because it epitomizes the fact. It couldn’t be simpler – all you need is club soda and raisins – but has easy-to-see, immediate, and delightful results.
First, fill a glass (or two) about 2/3 of the way with club soda.
Add about 4 raisins to each glass. Now watch what happens!
We immediately observed that the raisins sank to the bottom of the glass, but were very quickly covered in bubbles.
We only needed to wait a moment before we were rewarded…. with dancing raisins!
They swim up to the top, do a pirouette or two, and then sink back down. The best raisins did this over and over again. (Honestly, I’m not sure why some raisins were more “active” than others, but we definitely had some movers-and-shakers, and a few that just stayed inert).
I asked Travis why he thought the raisins were dancing, and he answered, “The bubbles!” He’s pretty much got it: the carbon-dioxide filled bubbles coat the raisins and rise to the top of the glass like all the bubbles in the water. Once they reach the top and pop, the raisin is released and sinks back down. For kids who can’t see molecules and atoms yet, it’s a neat visual of forces at work.
Of course Travis then needed to see what would happen if we dumped his entire snack pack of raisins into a glass. As you’d expect, the raisins mostly weighed one another down, but those on the top layer still danced for us!
Honestly, you’ll be entertained watching this experiment for quite some time; raisins are adorable dancers.
Note: We tried something similar with Halloween candy in October. What other foods can you make dance in a glass? Rice? Dried pasta? If you experiment further, please share in the comments!