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Sink or Float?

Experiment with objects that sink or float.


  • a large clear bin or bucket with water
  • two plastic bins labeled with picture signs: “Float” and “Sink”
  • various objects that float or sink (for example: rubber bands, sponges, pencils, plastic bottles with tops, wooden blocks, plastic straws, craft sticks, small plastic toys)


Encourage children to experiment with objects that sink or float. Have them make predictions, test them out, and then sort the objects in the  “Float” and “Sink” bin. Having children predict what will happen—and say why they think so—is a good way to get thinking going.