Reading Weighing Scales

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

1 - Getting Started ~4 mins

Look at this dial. The pointer has stopped between the 200 g mark and the 300 g mark. It is past 200 but it has not reached 300.

Is this right? A friend read it as "200 g". What would you say to them?

Teacher Notes

Display the frozen dial photo (pointer sitting between 200 g and 300 g) as pupils settle. Take two or three hands-up answers, not open call-outs.

Do not confirm the reading yet — the point is to unsettle "it must be one of the printed numbers". Listen for anyone who says "it's more than 200" and hold that thought for the model step.

👇 Mark your steps as done as you complete them.

+5 XP

2 - Watch and Notice ~8 mins

Illustration for Watch and Notice Before we read any pointer, we always ask one question first: how much is each little mark worth? The step size is how much each little mark on the dial is worth. On one dial each step might be 100 g; on another dial, each step might be 50 g.

Look at the dial on screen. Watch four readings in turn:

a dial in steps of 100 g, with the pointer landing right on a printed mark;
a dial in steps of 50 g that looks almost the same, but each little mark is worth only 50 g;
a bigger dial in steps of 100 g. Here the numbers pass 1000 g. We know 1000 g is the same as 1 kg, so once we count past 1000 we rename it: 1500 g becomes 1 kg 500 g;
a dial where the pointer stops halfway between two marks. When that happens, the weight is halfway between the two numbers too. Halfway between 700 g and 800 g is 750 g.

Notice how two dials can look almost the same, but the same pointer position means different weights once you know the step size.

Teacher Notes

Work each reading live on the demonstration scale where its graduation matches, and on the frozen dial photos for everything else. The frozen dial photos are the canonical version for the 50 g dial and for any reading a real kitchen scale cannot show — do not rely on a real scale graduating in 50 g steps. Do not narrate a script.

Cues, one per reading:

steps of 100 g — count aloud with the class: 100, 200, 300. Land on the mark.
steps of 50 g (from the photo) — same-looking dial, but ask first: what is each step worth here? Now count on in fifties.
past 1000 g (steps of 100 g) — remind the class 1 kg = 1000 g, so a reading of 1500 g is renamed 1 kg 500 g.
between marks — pointer stops halfway between 700 and 800; ask what number sits halfway, and draw out 750 g.

The recurring move to draw out: check the step size before you read the pointer. Hold out for a pupil to say it before you do.

👇 Mark your steps as done as you complete them.

+10 XP

3 - Write the Step Size in Your Copy ~3 mins

COPYBOOK MOMENT

Look at the three dials on the board, labelled 1, 2 and 3. In your maths copy, write down the step size and the weight for each one.

Write each line in this shape, filling in the two blanks yourself:

Dial 1: steps of ___ g, pointer on ___ g
Dial 2: steps of ___ g, pointer on ___ g
Dial 3: steps of ___ g, pointer on ___ g

Always write the step size first, then the weight.

Teacher Notes

Display three fresh dial pictures, clearly labelled 1, 2 and 3, so each pupil can match a copybook line to the picture they should read. You choose the three step sizes and pointer positions — nothing on screen fixes them, so use whatever your dial pictures actually show. Walk the room glancing at whether they wrote the step size first — this is whole-class copybook practice, not marking.

+10 XP

4 - Try It Together ~12 mins

First we learn how to find the step size by counting the little gaps on a dial. Then we read four dials together.

Watch this worked example on the board. Two printed numbers sit next to each other: 200 g and 300 g. The gap from 200 to 300 is 100 g in total. Count the little intervals (the small gaps) between those two printed numbers. There are 2 little intervals, so each step is worth 100 g ÷ 2 = 50 g. That is the step size. Only after we know the step size do we read where the pointer lands.

Now we try four dials together, one at a time. For each one, find the step size first by counting the intervals. Then read the pointer and say the weight:

a dial with the pointer on a printed mark;
a dial that looks similar to the first;
a bigger dial where the numbers pass 1000 g, then rename the reading in kilograms and grams;
a dial where the pointer stops halfway between two marks.

Hands-on Task

Teacher Notes

No live interactive on this step. Use a frozen dial photo or board drawing for the worked example, then the four shared readings.

Worked example first (step-size method): Point to printed marks 200 g and 300 g. Difference = 100 g. Count the little intervals between them out loud with the class (2 intervals). Step size = 100 ÷ 2 = 50 g. Say the recurring move: count the intervals before you read the pointer.

Quick contrast if useful: same printed numbers with only 1 interval between them means steps of 100 g.

Then the four readings (targets for you only): steps of 100 g, pointer on 400 g; steps of 50 g, pointer on 350 g; bigger dial, pointer on 1200 g, rename to 1 kg 200 g; steps of 100 g, pointer halfway between 700 g and 800 g, so 750 g.

For each reading, hold for a pupil to give the step size (by counting intervals) before anyone names the weight. Slip to watch: treating every little mark as 100 g without counting the intervals first.

+15 XP

5 - Class Challenge ~8 mins

Now we work through these readings together on the board. Say the step size out loud before you read each pointer:

a dial, read the pointer;
another dial, read the pointer;
a bigger dial that passes 1000 g, read the pointer and rename it in kilograms;
a dial where the pointer stops right between two marks, read the halfway weight.

Read the weighing-scale dial

Teacher Notes

This is the practice round, run on the board with the interactive scale in challenge mode. Show one reading at a time; the class says the step size out loud, then reads the pointer, and you confirm each answer with the on-screen ✓ before moving on. Keep the board work brisk rather than over-explaining.

The readings climb: an on-a-mark 100 g dial, then a 50 g dial (the step size changes), then past 1000 g (a rename to kg), then between two marks (a halfway reading). The last one catches people out, so save time for it.

+15 XP

Pupil practice

Module 4 · Measures: Length, Weight and Capacity Measures

Lesson 48 · Reading Weighing Scales

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Teacher Class Feed

1 - Getting Started ~4 mins

2 - Watch and Notice ~8 mins

3 - Write the Step Size in Your Copy ~3 mins

4 - Try It Together ~12 mins

Hands-on Task

5 - Class Challenge ~8 mins

Read the weighing-scale dial

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