So yesterday I spent about an hour in my neighborhood recycling rolloff (read dumpster) looking for clear plastic bottles to do this great lesson on buoyancy where the kids make their own Cartesian Diver. I was filling a tub with water when Susan's class can in from outside and they started asking about what we were going to do with the water. I asked if they knew why some things float and some sink? We got all kinds of opinions and the discussion was off and running. Some said metal sinks and wood floats. That got me thinking so I took a piece of aluminum foil and made a ball and it floated. It just felt wrong to step on such curiosity. I dropped my plans and started playing with them, the foil and some glass "jewels."
They were so totally engaged that we spent the next hour building "boats" out of aluminum foil and designing controlled experiments to see how well they floated. Terms like liquid, solid and crystallize came up. Again I'm reminded that we don't need to "hook" kids into exploring the world. This afternoon with Val's class I'm going to start out following their lead.
