On a trip to Michael's a few months ago, my daughter talked me into buying a $5 set of dinosaur skulls. We played with them at the beach this summer, pretending to be paleontologists digging up fossils in the sand. I rediscovered them again this week as I was doing our quarterly playroom purge, and as we head into winter, I thought it would be fun to move our fossil excavation to the Ice Caps.
To get us set up, I filled Dixie cups with water and dropped the dinosaur skulls in. Two of them I stuck right into the freezer; the other two I tried filling first with a bit of water (1/4" or so), freezing for 30 minutes, and then adding the dino skulls and more water--so we'd have a thicker layer of ice on top of the skulls. To be honest, it didn't seem to make a huge difference in the outcome, so I'd say you could go either way.
After 24 hours in the freezer, we popped them right out of the Dixie Cups. I placed them on top of a paper towel on a baking sheet to contain the melting ice.
My daughter and I discussed what tools a paleontologist would use to excavate fossils from ice. We decided on a (kid) knife, metal spoon, a pumpkin carver, and hot water. She started out using a straw to drop the water on the ice (a pipette or water dropper would be even better, if you have one)...
At this point, my daughter decided it was time to move to the Big Gun, so she grabbed the little pumpkin carving tool left over from Halloween (I watched her to make sure she was good to handle this on her own.)