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  • The Number System and Place Value
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For younger learners

  • Early Years Foundation Stage

Proof Through Words - Number

In this feature for Primary teachers, we offer a selection of numerical tasks that lend themselves to 'proof through words'. In the accompanying article, we outline three essential features of proof and illustrate what they might look like in the context of words, as opposed to algebraic symbols. The tasks we have included in this feature will help develop your learners' understanding of what constitutes a proof, so that they are well equipped on the mathematical journeys ahead.

You can watch a recording of the webinar in which we discussed the mathematical thinking which can be prompted by these activities.

You may also like to take a look at our Proof Through Words - Geometry feature which offers similar experiences but in a numerical context.

Why Dialogue Matters in Primary Proof

Age 5 to 11
In this article for Primary teachers, Ems explores three essential features of proof, all of which can be developed in the context of primary mathematics through talk.

Next-door Numbers

Age 5 to 7
Challenge Level Yellow star
Florence, Ethan and Alma have each added together two 'next-door' numbers. What is the same about their answers?

Two Numbers Under the Microscope

Age 5 to 7
Challenge Level Yellow star
This investigates one particular property of number by looking closely at an example of adding two odd numbers together.

Even and Odd

Age 5 to 7
Challenge Level Yellow star
This activity is best done with a whole class or in a large group. Can you match the cards? What happens when you add pairs of the numbers together?

Strike it Out

Age 5 to 11
Challenge Level Yellow star
Use your addition and subtraction skills, combined with some strategic thinking, to beat your partner at this game.

Take Three Numbers

Age 7 to 11
Challenge Level Yellow star
What happens when you add three numbers together? Will your answer be odd or even? How do you know?

An Easy Way to Multiply by 10?

Age 7 to 11
Challenge Level Yellow star
Do you agree with Badger's statements? Is Badger's reasoning 'watertight'? Why or why not?

Unravelling Sequences

Age 7 to 11
Challenge Level Yellow star
Can you describe what is happening as this program runs? Can you unpick the steps in the process?

Mathdoku

Age 7 to 11
Challenge Level Yellow star
Complete the Mathdoku grid using the clues. Can you convince us that the number you have chosen for each square has to be correct?

Three Neighbours

Age 7 to 14
Challenge Level Yellow starYellow star
Take three consecutive numbers and add them together. What do you notice?

Neighbourly Addition

Age 7 to 14
Challenge Level Yellow star
I added together some of my neighbours' house numbers. Can you explain the patterns I noticed?
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The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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