Mathematics

Intermediate

50 mins

Teacher/Student led

Learning Goals

Learning Outcomes

Lesson Files

+65 XP

Teacher-led from the board. Pupils do not need a device, but can follow on one.

What you need:
IWB/Projector/Large Screen

Written Subtraction of 2-digit Numbers with Renaming

Learn how to rename a ten as ten units when subtracting two-digit numbers, then check your answer by adding it back. You'll practise setting out subtraction in columns and deciding when renaming is needed.

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1 Getting Started
2 Watch and Notice
3 Try It Together
4 Work It in Your Copy
5 Class Challenge
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 17

Column subtraction

1 - Getting Started ~4 mins

Illustration for Getting Started Here is a subtraction: 52 − 17. Look at the units column first. We want to take 7 away from 2. Can we do it? What could we do when there are not enough units at the top to take away from?

👇 Mark your steps as done as you complete them.

+5 XP

2 - Watch and Notice ~9 mins

The interactive works through three subtractions in columns, renaming a ten each time. Watch what happens to the tens and units digits when we rename, and check that the number is still worth the same.

👇 Mark your steps as done as you complete them.

+10 XP

3 - Try It Together ~11 mins

Now we work through these three subtractions together on the board, one panel at a time: 45 − 19, then 63 − 28, then 81 − 79. Each one asks the same question first: are there enough units up top, or do we have to rename a ten? Say the answer aloud together before we fill in each column.

45 − 19

+15 XP

4 - Work It in Your Copy ~3 mins

COPYBOOK MOMENT

Illustration for Work It in Your Copy In your maths copy, set out these two subtractions in neat tens-and-units columns, one under the other:

64 − 28
73 − 46

Cross out and rename a ten where you must, then subtract each column. Finally, check each answer by adding it back to the smaller number.

+10 XP

5 - Class Challenge ~8 mins

Today we work through these numbers together on the board: 38 − 15, then 52 − 27, then 70 − 34, and finally 91 − 58. Check the units column carefully before you decide whether you need to rename a ten.

Class challenge: subtract with renaming

+15 XP

Pupil practice

Module 2 · The Four Operations: Mental and Written Number

Lesson 18 · Written Subtraction of 2-digit Numbers with Renaming

Download Activity Book page (PDF)

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