# Composition and calculation: numbers up to 10,000,000

Spine 1: Number, Addition and Subtraction – Topic 1.30

Primary KS2 Year 6
Mastery PD Materials

### Introduction

Building on segment 1.26, explore six-digit numbers that are not whole thousands, and then extend to seven-digit numbers; apply additive facts and strategies, including column algorithms, and rounding to these numbers.

### Teaching points

• Teaching point 1: Patterns seen in other powers of ten can be extended to the unit 1,000,000.

• Teaching point 2: Seven-digit numbers can be written, read and ordered by identifying the number of millions, the number of thousands and the number of hundreds, tens and ones.

• Teaching point 3: The digits in a number indicate its structure so it can be composed and decomposed.

• Teaching point 4: Knowledge of crossing thousands boundaries can be used to work to and across millions boundaries.

• Teaching point 5: Sometimes numbers are rounded as approximations to eliminate an unnecessary level of detail; rounded numbers are also used to give an estimate or average. At other times, precise readings are useful.

• Teaching point 6: Fluent calculation requires the flexibility to move between mental and written methods according to the specific numbers in a calculation.