Skip to content

Study Hub

Study Guides

This pupil-friendly study guide includes a unit summary, clear notes, common mistakes, and quick questions with answers.

Year 4 - Maths

Review using column addition to add 2- and 3-digit numbers by regrouping tens

Review of column addition and subtraction

Unit Summary

In this unit pupils will revisit column addition with regrouping and column subtraction with exchanging to solve problems.

Lesson Summary

You will learn to use column addition to add numbers by regrouping tens.

Key Notes

  • When using column addition, start by adding the numbers with the smallest place value first.
  • If the sum of the tens digits is ten or greater, regrouping is needed.
  • Any complete hundreds are regrouped into the hundreds column.

Vocabulary To Learn

  • Column addition: Column addition is a way of adding numbers by writing a number below another.
  • Regroup: The process of unitising and exchanging between place values is known as regrouping.

Common Mistakes To Avoid

  • Pupils may struggle to present regrouping in column addition.

3 Quick Questions (With Answers)

1. Solve this in steps: explain the method from this lesson and why each step matters.

When using column addition, start by adding the numbers with the smallest place value first. If the sum of the tens digits is ten or greater, regrouping is needed.

2. Use this key word in a maths sentence and explain it clearly. 'Column addition'

Column addition is a way of adding numbers by writing a number below another. Use this word when showing your method, then check your final answer is reasonable.

3. Spot and fix this common maths mistake.

Mistake: Pupils may struggle to present regrouping in column addition. Correction: Encourage pupils to talk about the process as they work through the problems. Model this in the lesson e.g. '5 tens add 7 tens is equal to 12 tens. 10 tens are regrouped as 1 hundred and written in the hundreds column.'.

More Lessons In This Unit

Browse all guides in the Year 4 Maths guide library.