Boats that float

Ages 3 to 5 Read and do together · about 20 minutes

Read together

A boat is a shape that floats.

Let us design one and test it.

Do it

1. Take a square of foil. Squeeze it into a tight ball and put it in water. It sinks.
2. Take another square. Shape it into a little boat with sides. It floats!
3. Add pretend cargo (large, light things). How much can your boat carry before it sinks?
4. Change the shape: wider, deeper, flatter. Test again and compare.

Talk about it

• Which shape carried the most?
• Why does the boat float?

For the grown-up

Foil floats when it is shaped like a boat because the boat pushes aside a lot of water, so the water pushes back. The same piece squeezed into a ball pushes aside very little. Let your child discover and compare, rather than explain at length.

Mark as done

← Previous lesson Next lesson →

Where this comes from

• NGSS Lead States, Next Generation Science Standards: For States, By States (National Academies Press, 2013), performance expectation K-2-ETS1-3 (analyze data from tests of two objects designed to solve the same problem)
• American Academy of Pediatrics, “Prevention of Drowning” (policy statement), Pediatrics (2019)

Written with AI assistance and checked against the sources listed. Please read it before sharing it with a child.