Year 3 - Maths
Find 10 more or 10 less than a given number
Bridging 100: counting on and back in 10s, adding/subtracting multiples of 10
Study Hub
Study Guides
This pupil-friendly study guide includes a unit summary, clear notes, common mistakes, and quick questions with answers.
Unit Summary
In this unit pupils will find pairs of number that compose 100. They will position 3-digit numbers on a number line and estimate their position on unmarked number lines. They will compare and order 3-digit numbers.
Lesson Summary
You will learn to find 10 more and 10 less than a number up to 200.
Key Notes
- When you count in tens, the ones digit stays the same.
- When you count in tens, the tens and hundreds digits may change.
- Knowledge of place value can help when counting forwards across the 100 boundary.
Vocabulary To Learn
- Multiple: The result of multiplying a number by another whole number.
- 100s boundary: The point at which the numbers change into 100s numbers, or from one set of hundreds to another.
Common Mistakes To Avoid
- Pupils may make errors when crossing the 100s boundary, either when adding or subtracting.
3 Quick Questions (With Answers)
1. Solve this in steps: explain the method from this lesson and why each step matters.
When you count in tens, the ones digit stays the same. When you count in tens, the tens and hundreds digits may change.
2. Use this key word in a maths sentence and explain it clearly. 'Multiple'
The result of multiplying a number by another whole number. 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 make errors when crossing the 100s boundary, either when adding or subtracting. Correction: Emphasise that ten 10s are equal to 100. When using base ten blocks, pupils should be encouraged to change ten 10s into one hundred.
More Lessons In This Unit
Browse all guides in the Year 3 Maths guide library.