Measuring length

Ages 6 to 8 Read together, then try alone · about 20 minutes

Read together

We measure length with a ruler. Start at zero, not at the edge.

Centimetres and metres are the units used in most of the world.

Do it

1. Guess the length of a pencil, a shoe and your hand span. Write your guesses.
2. Measure each with a ruler. Compare to your guess.
3. Measure the same thing with paper clips and then with a ruler. Why do the numbers differ?
4. Make a list of the longest and shortest things you found.

Talk about it

• How close was your guess?
• Why do we need a standard unit?

For the grown-up

Measuring with non-standard units first shows why standard units exist. Estimating before measuring builds number sense.

Mark as done

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Where this comes from

• National Governors Association Center for Best Practices and Council of Chief State School Officers, Common Core State Standards for Mathematics (2010), Grade 2 measurement and data 2.MD.A
• Bureau International des Poids et Mesures, The International System of Units (SI Brochure), the metre

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