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Heavier or Lighter?

What you’ll find out

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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 is not always heavy

Here is a big balloon and a small marble. Which one is heavier? The balloon is big, but it is mostly air, so it is light. The marble is small, but it is solid glass, so it is heavy for its size. Big does not always mean heavy.

Let the balance decide

A balance tells us which is heavier. Put one thing on each side: the heavier side goes down and the lighter side goes up. If the sides stay level, they weigh the same. You can measure with blocks too. One apple balances three blocks, so it weighs three blocks.

Curriculum links: NGSS 2-PS1-1 · CCSS K.MD.A.2