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Sink or Float

Build it⏱ 5 minutesAges 4-8

Things float when they are lighter than the water they push out of the way. Heavy, tight things like rocks sink.

Let's do it ↓

Grab this

  • A clear bowl of water
  • 5 small things: a spoon, a rock, a cork, a coin, a crayon
Supplies for Sink or Float

Do it in 3 steps

Sink or Float step 1
1

Line up your 5 things next to the bowl.

Sink or Float step 2
2

Guess out loud: will each one sink or float?

Sink or Float step 3
3

Drop them in one at a time. How many guesses were right?

Tinker Ted with a stopwatchDO IT WITH ME

Your turn! Beat the clock.

Press start, then put the screen down and build. We'll cheer when time is up.

5:00

⭐ Bonus round

Can you make a sinking thing float? Try putting the coin on the cork.

🧠 Why it works

Things float when they are lighter than the water they push out of the way. Heavy, tight things like rocks sink.

A grown up should be nearby for every challenge. Clean up together when you are done.

Did you do it?

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