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Number and algebra

  • The Number System and Place Value
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Geometry and measure

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Probability and statistics

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Working mathematically

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Advanced mathematics

  • Decision Mathematics and Combinatorics
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For younger learners

  • Early Years Foundation Stage

Surprise!

Surprise!

As you are working on a mathematical task, you might come across something unexpected that takes you by surprise.  

We hope these problems will surprise you and that you enjoy the challenge of explaining what is going on.

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?

Light the Lights 
Age 5 to 7
Challenge Level Yellow starYellow star

Investigate which numbers make these lights come on. What is the smallest number you can find that lights up all the lights?

How Would We Count? 
Age 5 to 11
Challenge Level Yellow star

An activity centred around observations of dots and how we visualise number arrangement patterns.

Square Surprise 
Age 5 to 11
Challenge Level Yellow star

Why do you think that the red player chose that particular dot in this game of Seeing Squares?

Pouring Problem 
Age 7 to 11
Challenge Level Yellow starYellow star

What do you think is going to happen in this video clip? Are you surprised?

Consecutive Numbers 
Age 7 to 14
Challenge Level Yellow star

An investigation involving adding and subtracting sets of consecutive numbers. Lots to find out, lots to explore.

Subtraction Surprise 
Age 7 to 14
Challenge Level Yellow star

Try out some calculations. Are you surprised by the results?

Related

  • Codebreakers
  • Tales of the Unexpected

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Digging Into Geometry

Dig deeply into geometrical ideas by having a go at the tasks in this Primary student feature.

More Playing with Numbers Upper Primary

More resources to support understanding multiplication and division through playing with numbers

Playing with Dice

We're starting the school year with some of our favourite dice activities.

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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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