Want to see your kid’s drawings float off the page? Have them try this science experiment from Sergei Urban, aka TheDadLab. He shares it with us from his book The Dad Lab: 50 Awesome Science Projects for Parents and Kids.
The activity is simple, yet impressive. (You’re pretty much guaranteed a “Whoooooooa.”) It’s science, it’s art, and it’s an excellent addition to your summer “boredom jar.”
What you’ll need:
Dry-erase markers (new ones work best)
A ceramic plate
What you’ll learn: Some pictures can float free of what you draw them on.
How long you’ll need: 20 minutes
How to do it:
Test all the dry-erase markers to make sure they will work for this activity: Draw one dot on a plate using each marker on and add some water. Only if the dots float the pens are suitable. Then, ask your child to draw on the plate. It’s best to colour in the drawing to make it hold together, although line drawings can work, too.
Pour some warm water slowly onto the plate.
The drawing should separate from the surface and float on top.
Try blowing it around with a straw.
Make a whole scene and watch the pieces float around one another!
Why not try...
After you have finished playing with the floating drawings, try putting paper on top of the water to transfer the drawings onto it.
What happens if...
You try this with regular felt-tip pens?
What’s going on?
This activity is aimed at promoting creativity more than teaching science. But it works because the ink in the dry-erase markers is a polymer — a kind of plastic — that dries into a solid film and doesn’t dissolve in water. It doesn’t stick very securely to the smooth ceramic plate (glass works well, too), so water will just lift it off.
Dry-erase markers do pretty much the opposite of normal markers. The ink in permanent markers sticks strongly to almost any surface, so you can’t get it off. But the whole point of dry-erase markers is that you can wipe off what you’ve drawn or written, because it’s so weakly stuck to the surface.
But there’s a second crucial reason why the drawing gets lifted off by water, which is that the film formed from the dried ink is less dense than water. That’s why, as the water slips under the drawing and lifts it free from the surface, the drawing gets carried to the top of the water like a bobbing cork.
This experiment is adapted from TheDadLab by arrangement with TarcherPerigee, a member of Penguin Group (USA) LLC, A Penguin Random House Company. Copyright © 2019, Sergei Urban.