Why Some Things Float
- Physics
- Ages 6–8 · Grades 1–2
- Hands-on experiment
What you’ll find out
- Floating is not decided by how heavy something is.
- The same material can float or sink depending on its shape.
No sign-up and no real names. In the lesson you check your understanding as you read, run the experiment yourself, and practise until it sticks.
Big things float, small things sink
Put different things in a tank of water. Some float and some sink. A big apple floats, and a tiny coin goes straight to the bottom. So it is not about size, and it is not about being heavy.
The same clay, twice
Try this. Roll some clay into a lump and it sinks. Now press the same clay into a boat shape and it floats. It is the same clay and the same weight. Only the shape changed, and that turned out to be what mattered.
Curriculum links: NGSS 2-PS1-1