Reasoning, convincing and proving

There are 458 NRICH Mathematical resources connected to Reasoning, convincing and proving
Noah
problem

Noah

Age
5 to 7
Challenge level
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Noah saw 12 legs walk by into the Ark. How many creatures did he see?
Adding all nine
problem

Adding all nine

Age
11 to 14
Challenge level
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Make a set of numbers that use all the digits from 1 to 9, once and once only. Add them up. The result is divisible by 9. Add each of the digits in the new number. What is their sum? Now try some other possibilities for yourself!
Calendar Capers
problem

Calendar Capers

Age
11 to 14
Challenge level
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Choose any three by three square of dates on a calendar page...
Symmetric Tangles
article

Symmetric Tangles

The tangles created by the twists and turns of the Conway rope trick are surprisingly symmetrical. Here's why!
Primary Proof?
article

Primary Proof?

Proof does have a place in Primary mathematics classrooms, we just need to be clear about what we mean by proof at this level.