I'm a bit late with this one, but Sunday September 20 is International Rock Flipping Day. Visit Wanderin' Weeta blog for full details.
Basically you go outside and look under a rock or two. Record what you see by drawing, painting, taking photographs or recording in your nature journal. If you live where there might be poisonous creatures under there, like scorpions or snakes, use gloves and/or a bar to flip the rocks.
When you are done, carefully return the rock to its original position.
If you blog about it, let them know.
Now wasn't that fun?