Length: Metres and Choosing the Right Unit

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1 Getting Started
2 Watch and Notice
3 Try It Together
4 Sort the Lengths in Your Copy
5 Class Challenge
6 What Did We Notice?
7 What's Next
Pupil practice

1 - Getting Started ~4 mins

Look at the metre stick standing beside the classroom door. Would you measure how long our corridor is in centimetres, or in metres? Hands up: which one would be easier, and why?

Teacher Notes

Stand a real metre stick beside the door as pupils settle. Take three hands-up answers, not open call-outs. Steer toward metres are easier for big things without naming the rule yet — that comes in the next step.

👇 Mark your steps as done as you complete them.

+5 XP

2 - Watch and Notice ~8 mins

Illustration for Watch and Notice Watch the metre ruler on the screen. A whole metre lines up exactly with the metre stick — one stick, one metre. A length of corridor takes two metre sticks laid end to end. Now look at the ruler the teacher is holding: a desk is about 60 centimetres, less than one metre stick, and a pencil is only about 12 centimetres. The long things suit metres; the short things suit centimetres.

Teacher Notes

The screen shows only the metre-scale lengths the ruler can display — one metre lining up with the stick, and a corridor taking two sticks. Hold the real metre stick against the screen for these.

For the short-things half of the contrast, hold up the real classroom ruler at the front: a desk is less than one metre stick; a pencil is tiny. The short examples are carried by your real ruler, not the screen.

Do not move on until the class can say which examples suit metres and which suit centimetres.

👇 Mark your steps as done as you complete them.

+10 XP

3 - Try It Together ~11 mins

Going outside

Whole class in whatever flat space your school has room in — yard, hall, or corridor — split into three groups, each with its own metre stick and a copybook to record. Before the lesson, choose three lengths to measure: a Short one (a bench), a Medium one (the width of the space), a Long one (about 10 metres along the longest wall).

Materials

metre stick
copybook
pencil

Plan

In your group, estimate each length in whole metres before you measure it — say your guess aloud.
Lay the metre stick flat along the length, mark where it ends, then lift it and lay it again from that mark.
Count one whole metre each time you lay the stick down: one, two, three.
Stop when the next metre would run past the end, and say how many whole metres you counted.
Swap who lays the stick for the next length, and compare your count with your group's estimate.

If you can’t go out: indoor alternative

If the yard is unusable, run the same Short / Medium / Long structure indoors — a bench for the Short length, the width of the hall for the Medium, the full length of the corridor for the Long.

Teacher Notes

This round is for pupils to measure with the metre stick in your school's open space. Split the class into three groups, each with its own metre stick, all measuring in parallel — that way every pupil gets a hands-on turn within the eleven minutes. Circulate and catch slips on the spot; the group reads each count aloud and you reconcile any disagreement as you pass each group.

Before the lesson, choose a flat space with room for a stretch of about 10 metres (yard, hall, or corridor) and the three lengths: a bench (Short), the width of the space (Medium), and a long wall about 10 metres (Long). Within each group, one pupil lays the metre stick end over end while the rest count whole metres aloud, then they swap for the next length. Watch for the stick lifting before the next mark is made — the slip that loses a metre.

+15 XP

4 - Sort the Lengths in Your Copy ~3 mins

COPYBOOK MOMENT

Illustration for Sort the lengths in your copy In your maths copy, make two columns headed "metres" and "centimetres". Then sort these six lengths into the column you would use to measure each one:

a hurley
a finger
the classroom
a book
the yard
a crayon

Teacher Notes

Walk the room glancing at which column each length lands in — this is whole-class copybook practice, not marking. Watch for a hurley going into centimetres; ask that pupil to picture how many metre sticks long it is.

+10 XP

5 - Class Challenge ~8 mins

Going outside

Whole class in your school's open space, split into three groups, each with its own metre stick and copybooks to record estimates and measurements. Mark three routes of rising length with chalk or masking tape before the lesson: the width of the classroom, the length of the classroom, and the longest wall.

Materials

metre stick
copybook
pencil
chalk or masking tape (to mark routes)

Plan

Write your estimate in whole metres for the width of the classroom, then measure it.
Write your estimate for the length of the classroom, then measure it.
Write your estimate for the longest wall, then measure it.
For each one, say how close your estimate was — and which estimate was closest of all.
Swap who lays the metre stick after each length so everyone gets a turn.

If you can’t go out: indoor alternative

If the yard is unusable, mark the same three rising lengths indoors — across the classroom, along the classroom, and along the full length of the corridor for the longest.

Teacher Notes

This round is the practice bank — the three groups measure each route in parallel, with each group confirming its count aloud at the end. The estimate-then-measure cycle is the heart of it, so keep the rhythm brisk.

Push for whole-metre estimates even when pupils are unsure — a rough guess they can check is the point. Watch for estimates getting closer as the lesson goes on, and name that out loud as a success.

+15 XP

6 - What Did We Notice? ~3 mins

MATHS TALK

How do you decide whether to reach for the ruler or the metre stick? Think of one thing you would measure with each.

Teacher Notes

Listen for pupils naming the size of the object as the deciding factor, not the tool nearest to hand. Revoice a strong answer: so the long things suit the metre stick and the short things suit the ruler. Head off the idea that bigger is always better — a finger in metres would be a tiny fraction, hard to say.

+10 XP

7 - What's Next ~2 mins

What we learned

Long things, like the corridor or the yard, are easier to measure in metres.
Short things, like a pencil or a finger, are easier to measure in centimetres.
We lay the metre stick end over end and count whole metres.

Coming up

Next we will look at how metres and centimetres are linked, so we can swap between them.

Teacher Notes

Close by holding the metre stick beside the ruler one more time so pupils carry the size difference into the next lesson on renaming m and cm.

+5 XP

Pupil practice

Module 4 · Measures: Length, Weight and Capacity Measures

Lesson 45 · Length: Metres and Choosing the Right Unit

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Teacher Class Feed

1 - Getting Started ~4 mins

2 - Watch and Notice ~8 mins

3 - Try It Together ~11 mins

Materials

Plan

4 - Sort the Lengths in Your Copy ~3 mins

5 - Class Challenge ~8 mins

Materials

Plan

6 - What Did We Notice? ~3 mins

7 - What's Next ~2 mins

What we learned

Coming up

Unlock the full learning experience

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