Sinking and Floating

Its a simple one this week, we are looking at sinking and floating. My children love playing with water so had a great time testing things today.

What you need:

  • a large bowl of water
  • Objects to test (anything you like, but good to pick some solid and some hollow)
  • Fill the bowl or container about 2/3 full of water.
  •  Gently place the objects on the water, some objects will float when you place them on the water gently, but sink when you drop them.

Can you predict which objects will float and which will sink?

Can you also design a table to record your results?

The Science bit.

Whether an object floats or sinks depends on its density. Density is how tightly packed the material inside an object is. Just because something is heavy does not mean it will sink. For example, ships are very heavy but not very dense so they float.





Something else to try would be to make a boat from plasticine and show how marbles or something similar sink on their own, but hopefully float when inside the boat.

Author: Emma Vanstone

Science Sparks, is a site dedicated to making Science fun for kids. I’d love you to follow me on my Google Profile+.

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