Have you seen the toothpick star trick?
It's possible you might have, it seems to be all over the Internet. It was a new one to us, though. The kids got such a kick out of, I thought I'd pass it along to you, just in case you haven't seen it yet, either.
All you need is 5 wooden toothpicks (unwaxed), a plate, or counter top, a glass of water, and a drinking straw.
Bend the toothpicks in half, without breaking completely apart.
Place them on the plate, with the partially broken parts touching to form a circle.
Use the straw, as an eye dropper, to drop one, or two drops of water into the center of the circle.
As the wood absorbs the water (which happens quickly), and passes it from the compressed, broken ends, toward the pointy ends, by capillary action, the toothpicks try to straighten out...
...forming into a star shape.
Steve Spangler has a video demonstration of this trick on his site, and about the best scientific explanation of what's happening, that we could find.
It's great to be a homeschooler.