Mathematics

Intermediate

50 mins

Teacher/Student led

Learning Goals

Learning Outcomes

Lesson Files

+75 XP

Teacher-led from the board — pupils need no device

What you need:
IWB/Projector/Large Screen

Converting Mass Units

Learn to convert between kilograms and grams using the ×1000 and ÷1000 rules. Explore how small masses become small decimals when written in kilograms.

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

Your turn

Your teacher is running this lesson on the board. Here is the part you can try yourself.

Your written work is on page 54

Unit converter

1 - Getting Started ~4 mins

Illustration for Getting Started Here is a bag of flour. The label says 2.5 kg. If we wanted to write that same mass in grams instead, what would we write?

👇 Mark your steps as done as you complete them.

+5 XP

2 - Watch and Notice ~9 mins

The interactive shows a conversion ladder between kilograms and grams. Kilograms sit one rung above grams, and each rung down shows the digits moved three place-value columns to the left, that is × 1000. Look at each example, then hands up to say which way the digits moved.

👇 Mark your steps as done as you complete them.

+10 XP

3 - Try It Together ~11 mins

Key point

Today we work these conversions together on the ladder. Say whether each one goes × 1000 or ÷ 1000 before we check it, and watch which way the digits slide. The whole class says the rule together before we tap Check.

1.75 kg → g
500 g → kg
0.4 kg → g
8 g → kg

Convert the mass: kg and g

+10 XP

4 - Work the Conversions in Your Copy ~2 mins

COPYBOOK MOMENT

In your maths copy, work each conversion as kg ↔ g. Draw a little arrow between them and label the arrow ×1000 or ÷1000 to show which way you went.

2.5 kg → g
0.25 kg → g
500 g → kg
75 g → kg

+10 XP

5 - Class Challenge ~8 mins

Key point

Today we work through these conversions together. Say × 1000 or ÷ 1000 before each Check:

3 kg → g
250 g → kg
1.2 kg → g
0.75 kg → g
6 g → kg (the tricky one)

Match the mass

+15 XP

Pupil practice

Module 4 · Measures: Length, Mass, Capacity, Area, Volume Measures

Lesson 57 · Converting Mass Units

Download Activity Book page (PDF)

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Converting Mass Units

Teacher Class Feed

1 - Getting Started ~4 mins

2 - Watch and Notice ~9 mins

3 - Try It Together ~11 mins

Convert the mass: kg and g

4 - Work the Conversions in Your Copy ~2 mins

5 - Class Challenge ~8 mins

Match the mass

Unlock the full learning experience

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