Magnitude comparison

How to augment class level teaching to focus on the understanding of magnitude.

In a nutshell: Magnitude comparison

Magnitude comparison is the ability to decide which number is more, less, or the same.

In the early years, children begin by comparing quantities of objects while they are developing number awareness. In Foundation, students compare and work with numbers to at least 20. In Year 1, students extend this work to numbers to 100, including comparing two-digit numerals using emerging place-value understanding. Across both year levels, students increasingly compare numerals directly, such as deciding whether 8 or 12, 34 or 43, or 76 or 79 is more.

The main instructional goal is for students to compare the value of numbers and numerals, not just collections of objects. Materials such as counters, fingers, ten-frames, number tracks, and base-10 blocks are useful, but they should be used to help children prove or explain a number comparison.

A strong instructional routine is:

Show two numerals → ask which number is more or less → have students say the comparison sentence → use a representation to prove how they know.

This guidance is designed to follow from ENSSA magnitude comparison testing when there is a class-wide need to improve the fluent comparison of number magnitude.

See also: Magnitude estimation.

Guidance and resources

Use the resources below to move from understanding the skill to selecting an instructional response.

• Begin with the Teaching Guidance and Background to clarify the instructional goal and progression.
• Use the Vocabulary, Representations and Stem Sentences guide to support consistent teacher language and student explanations.
• Use Review and Practice routines when students are accurate and need frequent classwide practice.
• Use Explicit Instruction Routines when students need modelling, guided practice, correction, and supported independent practice.
• The Implementation Summary provides a quick checklist for planning and review.

Downloadable guides

Use these linked Science of Learning resources to plan the instructional response.