• Mastery PD Materials

The structure of the number system

Theme 1 comprises four core concepts: place value, estimation and rounding; properties of number; ordering and comparing; simplifying and manipulating expressions, equations and formulae.

The structure of the number system

The links immediately below take you to pages dedicated to each core concept, which include all the classroom and professional development resources you need.

Underneath the links to the core concept pages, you can download an overview of the entire theme, and a single download of all core concept documents within the theme.

1.1 Place value, estimation and rounding

Core concept 1.1 covers the structure of our place-value system (particularly as it relates to decimals) and rounding numbers to a required number of decimal places or significant figures.

1.2 Properties of number

Core concept 1.2 focuses on factors, multiples and primes, exploring various representations to support understanding of highest common factors and lowest common multiples.

1.3 Ordering and comparing

Core concept 1.3 covers the conversion of decimals to fractions (and vice versa), ordering positive and negative integers, fractions and decimals, and the expression of numbers in standard form.


  • Secondary
  • KS3
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