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Number and algebra

  • The Number System and Place Value
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Probability and statistics

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Working mathematically

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Advanced mathematics

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For younger learners

  • Early Years Foundation Stage

Cracking Codes

Cracking Codes

When a secret agent wants to send a message, they write it in code so their enemies can't read it. Codebreakers need to develop mathematical skills like working backwards, being systematic, and ruling out possibilities in order to crack enemy codes and save the day. These problems will give you the chance to train your brain in order to become a better code cracker!

Satisfying Statements 
Age 11 to 14
Challenge Level Yellow star

Can you find any two-digit numbers that satisfy all of these statements?

Statement Snap 
Age 7 to 14
Challenge Level Yellow star

You'll need to know your number properties to win a game of Statement Snap...

Charlie's Delightful Machine 
Age 11 to 16
Challenge Level Yellow star

Here is a machine with four coloured lights. Can you develop a strategy to work out the rules controlling each light?

A Little Light Thinking 
Age 14 to 16
Challenge Level Yellow star

Here is a machine with four coloured lights. Can you make two lights switch on at once? Three lights? All four lights?

Related

  • Number Teasers
  • Hidden Treasures

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Patterns in Number Sequences

These resources are designed to get you thinking about number sequences and patterns.

Secondary Student Latest

Latest list for the Lower Secondary Student page

Curriculum Topics

Problems organised by curriculum topic for lower secondary students.

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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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