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Measuring length (age 7+)

Measure the length of an object by selecting and using appropriate tools such as rulers, yardsticks, metre sticks, and measuring tapes

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What a learner can do afterwards

  • Choose the most appropriate tool for measuring a given object
  • Align the zero mark of a ruler with the end of the object and read the measurement
  • Measure lengths in inches, feet, centimetres, and metres using the correct tool

The lesson

You already know how to measure with a ruler. A ruler is great for a pencil or a book. But some things are too long for a short ruler. For those, you need a longer tool: a yardstick, a metre stick, or a measuring tape.

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Line up the ribbon's end with the 0 mark. Read where the other end lands: 9 cm.
Try it together

Ana needs to measure a piece of fabric that is about 80 cm long. Her ruler only goes up to 30 cm, so she picks a measuring tape instead. She lines up the zero end of the tape with one edge of the fabric and reads 80 cm at the other edge.

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Good to know

Always start at the 0 mark, not the edge of the ruler. And match the tool to the job: short ruler for small things, tape measure or metre stick for long ones.

Pick a tool long enough for the job, line up its zero mark, and read the length in the right unit.

Watch it

Where it sits

Where this leads

Jobs that lean on this skill. Follow one to see everything it is built on.

Then practise

8 questions wait behind this lesson, each with its answer explained. Every answer feeds the sky: stars light as they are learned, and dim when it is time to come back.

Measuring length (age 7+) · Mathematics, ages 7 to 8 · LightMySky