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Number and algebra

  • The Number System and Place Value
  • Calculations and Numerical Methods
  • Fractions, Decimals, Percentages, Ratio and Proportion
  • Properties of Numbers
  • Patterns, Sequences and Structure
  • Algebraic expressions, equations and formulae
  • Coordinates, Functions and Graphs

Geometry and measure

  • Angles, Polygons, and Geometrical Proof
  • 3D Geometry, Shape and Space
  • Measuring and calculating with units
  • Transformations and constructions
  • Pythagoras and Trigonometry
  • Vectors and Matrices

Probability and statistics

  • Handling, Processing and Representing Data
  • Probability

Working mathematically

  • Thinking mathematically
  • Developing positive attitudes
  • Cross-curricular contexts

Advanced mathematics

  • Decision Mathematics and Combinatorics
  • Advanced Probability and Statistics
  • Mechanics
  • Calculus

For younger learners

  • Early Years Foundation Stage

KS3 Roadshow

Two Stones

Age 5 to 18

This game is known as Pong hau k'i in China and Ou-moul-ko-no in Korea. Find a friend to play or try the interactive version online.

Matching Fractions, Decimals and Percentages

Age 7 to 14
Challenge Level Yellow star

Can you match pairs of fractions, decimals and percentages, and beat your previous scores?

Dozens

Age 7 to 14
Challenge Level Yellow star

Can you select the missing digit(s) to find the largest multiple?

More Less Is MoreLive

Age 7 to 14
Challenge Level Yellow star

In each of these games, you will need a little bit of luck, and your knowledge of place value to develop a winning strategy.

Twinkle Twinkle

Age 7 to 14
Challenge Level Yellow star

A game for 2 people. Take turns placing a counter on the star. You win when you have completed a line of 3 in your colour.

Got It

Age 7 to 14
Challenge Level Yellow starYellow star

A game for two people, or play online. Given a target number, say 23, and a range of numbers to choose from, say 1-4, players take it in turns to add to the running total to hit their target.

Remainders

Age 7 to 14
Challenge Level Yellow starYellow star

I'm thinking of a number. My number is both a multiple of 5 and a multiple of 6. What could my number be?

Fifteen

Age 7 to 14
Challenge Level Yellow starYellow star

Can you spot the similarities between this game and other games you know? The aim is to choose 3 numbers that total 15.

Number Sandwiches

Age 7 to 14
Challenge Level Yellow starYellow star

Can you arrange the digits 1, 1, 2, 2, 3 and 3 to make a Number Sandwich?

Tea Cups

Age 7 to 14
Challenge Level Yellow starYellow starYellow star

Place the 16 different combinations of cup/saucer in this 4 by 4 arrangement so that no row or column contains more than one cup or saucer of the same colour.

Factors and Multiples Game

Age 7 to 16
Challenge Level Yellow star

A game in which players take it in turns to choose a number. Can you block your opponent?

Pentanim

Age 7 to 16
Challenge Level Yellow starYellow star

A game for 2 players with similarities to NIM. Place one counter on each spot on the games board. Players take it is turns to remove 1 or 2 adjacent counters. The winner picks up the last counter.

Low Go

Age 7 to 16
Challenge Level Yellow starYellow star

A game for 2 players. Take turns to place a counter so that it occupies one of the lowest possible positions in the grid. The first player to complete a line of 4 wins.

Colour in the Square

Age 7 to 16
Challenge Level Yellow starYellow star

Can you put the 25 coloured tiles into the 5 x 5 square so that no column, no row and no diagonal line have tiles of the same colour in them?

Prime Magic

Age 7 to 16
Challenge Level Yellow starYellow star

Place the numbers 1, 2, 3,..., 9 one on each square of a 3 by 3 grid so that all the rows and columns add up to a prime number. How many different solutions can you find?

Dominoes

Age 7 to 16
Challenge Level Yellow starYellow star

Everthing you have always wanted to do with dominoes! Some of these games are good for practising your mental calculation skills, and some are good for your reasoning skills.

Domino Magic Rectangle

Age 7 to 16
Challenge Level Yellow starYellow starYellow star

An ordinary set of dominoes can be laid out as a 7 by 4 magic rectangle in which all the spots in all the columns add to 24, while those in the rows add to 42. Try it! Now try the magic square...

Eight Dominoes

Age 7 to 16
Challenge Level Yellow starYellow starYellow star

Using the 8 dominoes make a square where each of the columns and rows adds up to 8

Air Nets

Age 7 to 18
Challenge Level Yellow star

Can you visualise whether these nets fold up into 3D shapes? Watch the videos each time to see if you were correct.

Guess my Quad

Age 11 to 14
Challenge Level Yellow star

How many questions do you need to identify my quadrilateral?

Sticky Numbers

Age 11 to 14
Challenge Level Yellow star

Can you arrange the numbers 1 to 17 in a row so that each adjacent pair adds up to a square number?

Cryptarithms

Age 11 to 14
Challenge Level Yellow star

Can you crack these cryptarithms?

Shady Symmetry

Age 11 to 14
Challenge Level Yellow star

How many different symmetrical shapes can you make by shading triangles or squares?

Olympic Records

Age 11 to 14
Challenge Level Yellow star

Can you deduce which Olympic athletics events are represented by the graphs?

Factors and Multiples Puzzle

Age 11 to 14
Challenge Level Yellow star

Using your knowledge of the properties of numbers, can you fill all the squares on the board?

Gabriel's Problem

Age 11 to 14
Challenge Level Yellow star

Gabriel multiplied together some numbers and then erased them. Can you figure out where each number was?

Dicey Operations

Age 11 to 14
Challenge Level Yellow star

Who said that adding, subtracting, multiplying and dividing couldn't be fun?

Consecutive Seven

Age 11 to 14
Challenge Level Yellow star

Can you arrange these numbers into 7 subsets, each of three numbers, so that when the numbers in each are added together, they make seven consecutive numbers?

Add to 200

Age 11 to 14
Challenge Level Yellow star

By selecting digits for an addition grid, what targets can you make?

Special Numbers

Age 11 to 14
Challenge Level Yellow star

My two digit number is special because adding the sum of its digits to the product of its digits gives me my original number. What could my number be?

Odds, Evens and More Evens

Age 11 to 14
Challenge Level Yellow star

Alison, Bernard and Charlie have been exploring sequences of odd and even numbers, which raise some intriguing questions...

Fractions Jigsaw

Age 11 to 14
Challenge Level Yellow star

A jigsaw where pieces only go together if the fractions are equivalent.

Forwards Add Backwards

Age 11 to 14
Challenge Level Yellow star

What happens when you add a three digit number to its reverse?

Magic Letters

Age 11 to 14
Challenge Level Yellow star

Charlie has made a Magic V. Can you use his example to make some more? And how about Magic Ls, Ns and Ws?

Reflecting Squarely

Age 11 to 14
Challenge Level Yellow star

In how many ways can you fit all three pieces together to make shapes with line symmetry?

American Billions

Age 11 to 14
Challenge Level Yellow star

Play the divisibility game to create numbers in which the first two digits make a number divisible by 2, the first three digits make a number divisible by 3...

Olympic Measures

Age 11 to 14
Challenge Level Yellow star

These Olympic quantities have been jumbled up! Can you put them back together again?

Sociable Cards

Age 11 to 14
Challenge Level Yellow star

Move your counters through this snake of cards and see how far you can go. Are you surprised by where you end up?

Can They Be Equal?

Age 11 to 14
Challenge Level Yellow star

Can you find rectangles where the value of the area is the same as the value of the perimeter?

Cinema Problem

Age 11 to 14
Challenge Level Yellow star

A cinema has 100 seats. Show how it is possible to sell exactly 100 tickets and take exactly £100 if the prices are £10 for adults, 50p for pensioners and 10p for children.

Substitution Cipher

Age 11 to 14
Challenge Level Yellow star

Find the frequency distribution for ordinary English, and use it to help you crack the code.

Colourful Cube

Age 11 to 14
Challenge Level Yellow star

A colourful cube is made from little red and yellow cubes. But can you work out how many of each?

Frogs

Age 11 to 14
Challenge Level Yellow star

How many moves does it take to swap over some red and blue frogs? Do you have a method?

Multiples Sudoku

Age 11 to 14
Challenge Level Yellow star

Each clue in this Sudoku is the product of the two numbers in adjacent cells.

Cayley

Age 11 to 14
Challenge Level Yellow star

The letters in the following addition sum represent the digits 1 ... 9. If A=3 and D=2, what number is represented by "CAYLEY"?

What Numbers Can We Make?

Age 11 to 14
Challenge Level Yellow star

Imagine we have four bags containing a large number of 1s, 4s, 7s and 10s. What numbers can we make?

1 Step 2 Step

Age 11 to 14
Challenge Level Yellow starYellow star

Liam's house has a staircase with 12 steps. He can go down the steps one at a time or two at time. In how many different ways can Liam go down the 12 steps?

3388

Age 11 to 14
Challenge Level Yellow starYellow star

Using some or all of the operations of addition, subtraction, multiplication and division and using the digits 3, 3, 8 and 8 each once and only once make an expression equal to 24.

Making Rectangles, Making Squares

Age 11 to 14
Challenge Level Yellow starYellow star

How many differently shaped rectangles can you build using these equilateral and isosceles triangles? Can you make a square?

Tower of Hanoi

Age 11 to 14
Challenge Level Yellow starYellow star

The Tower of Hanoi is an ancient mathematical challenge. Working on the building blocks may help you to explain the patterns you notice.

Stars

Age 11 to 14
Challenge Level Yellow starYellow star

Can you work out what step size to take to ensure you visit all the dots on the circle?

Zin Obelisk

Age 11 to 14
Challenge Level Yellow starYellow star

In the ancient city of Atlantis a solid rectangular object called a Zin was built in honour of the goddess Tina. Your task is to determine on which day of the week the obelisk was completed.

Peaches Today, Peaches Tomorrow...

Age 11 to 14
Challenge Level Yellow starYellow star

A monkey with peaches, keeps a fraction of them each day, gives the rest away, and then eats one. How long can his peaches last?

Always a Multiple?

Age 11 to 14
Challenge Level Yellow starYellow star

Think of a two digit number, reverse the digits, and add the numbers together. Something special happens...

Squares in Rectangles

Age 11 to 14
Challenge Level Yellow starYellow star

A 2 by 3 rectangle contains 8 squares and a 3 by 4 rectangle contains 20 squares. What size rectangle(s) contain(s) exactly 100 squares? Can you find them all?

Overlaps

Age 11 to 14
Challenge Level Yellow starYellow star

Can you find ways to put numbers in the overlaps so the rings have equal totals?

Route to Infinity

Age 11 to 14
Challenge Level Yellow starYellow star

Can you describe this route to infinity? Where will the arrows take you next?

Bow Tie

Age 11 to 14
Challenge Level Yellow starYellow star

Show how this pentagonal tile can be used to tile the plane and describe the transformations which map this pentagon to its images in the tiling.

Fibonacci Surprises

Age 11 to 14
Challenge Level Yellow starYellow star

Play around with the Fibonacci sequence and discover some surprising results!

Where Can We Visit?

Age 11 to 14
Challenge Level Yellow starYellow star

Charlie and Abi put a counter on 42. They wondered if they could visit all the other numbers on their 1-100 board, moving the counter using just these two operations: x2 and -5. What do you think?

Temperature

Age 11 to 14
Challenge Level Yellow starYellow star

Is there a temperature at which Celsius and Fahrenheit readings are the same?

Opposite Vertices

Age 11 to 14
Challenge Level Yellow starYellow star

Can you recreate squares and rhombuses if you are only given a side or a diagonal?

Soma - So Good

Age 11 to 14
Challenge Level Yellow starYellow starYellow star

Can you mentally fit the 7 SOMA pieces together to make a cube? Can you do it in more than one way?

Tourism

Age 11 to 14
Challenge Level Yellow starYellow starYellow star

If you can copy a network without lifting your pen off the paper and without drawing any line twice, then it is traversable. Decide which of these diagrams are traversable.

Domino Tetrads

Age 11 to 14
Challenge Level Yellow starYellow starYellow star

Is it possible to use all 28 dominoes arranging them in squares of four? What patterns can you see in the solution(s)?

Cuboids

Age 11 to 14
Challenge Level Yellow starYellow starYellow star

Can you find a cuboid that has a surface area of exactly 100 square units. Is there more than one? Can you find them all?

Are We Nearly There?

Age 11 to 16

Can you describe the route followed by the arrows?

Getting Round the City

Age 11 to 16

In a city with a grid system of roads, how do you get from A to B?

Take Ten Sticks

Age 11 to 16
Challenge Level Yellow star

Take ten sticks in heaps any way you like. Make a new heap using one from each of the heaps. By repeating that process could the arrangement 7 - 1 - 1 - 1 ever turn up, except by starting with it?

What's it Worth?

Age 11 to 16
Challenge Level Yellow star

There are lots of different methods to find out what the shapes are worth - how many can you find?

Square It

Age 11 to 16
Challenge Level Yellow star

Players take it in turns to choose a dot on the grid. The winner is the first to have four dots that can be joined to form a square.

Marbles in a Box

Age 11 to 16
Challenge Level Yellow starYellow star

How many winning lines can you make in a three-dimensional version of noughts and crosses?

Connect Three

Age 11 to 16
Challenge Level Yellow starYellow star

In this game the winner is the first to complete a row of three. Are some squares easier to land on than others?

Who's Who?

Age 11 to 16
Challenge Level Yellow starYellow star

Can you solve the clues to find out who's who on the friendship graph?

Product Sudoku

Age 11 to 16
Challenge Level Yellow starYellow star

The clues for this Sudoku are the product of the numbers in adjacent squares.

Take Three from Five

Age 11 to 16
Challenge Level Yellow starYellow star

Caroline and James pick sets of five numbers. Charlie tries to find three that add together to make a multiple of three. Can they stop him?

Nine Colours

Age 11 to 16
Challenge Level Yellow starYellow starYellow star

Can you use small coloured cubes to make a 3 by 3 by 3 cube so that each face of the bigger cube contains one of each colour?

Two and Two

Age 11 to 16
Challenge Level Yellow starYellow starYellow star

How many solutions can you find to this sum? Each of the different letters stands for a different number.

Times Right

Age 11 to 16
Challenge Level Yellow starYellow starYellow star

Using the digits 1, 2, 3, 4, 5, 6, 7 and 8, mulitply a two two digit numbers are multiplied to give a four digit number, so that the expression is correct. How many different solutions can you find?

One, Three, Five, Seven

Age 11 to 16
Challenge Level Yellow starYellow starYellow star

A game for 2 players. Set out 16 counters in rows of 1,3,5 and 7. Players take turns to remove any number of counters from a row. The player left with the last counter looses.

Last Biscuit

Age 11 to 18
Challenge Level Yellow starYellow star

Can you find a strategy that ensures you get to take the last biscuit in this game?

Crossing the Bridge

Age 11 to 18
Challenge Level Yellow starYellow star

Four friends must cross a bridge. How can they all cross it in just 17 minutes?

Instant Insanity

Age 11 to 18
Challenge Level Yellow starYellow starYellow star

Given the nets of 4 cubes with the faces coloured in 4 colours, build a tower so that on each vertical wall no colour is repeated, that is all 4 colours appear.

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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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