List

Visualising - Upper Secondary

Pumpkin Patch
game

Pumpkin patch

Age
5 to 18
A game for two players based on a game from the Somali people of Africa. The first player to pick all the other's 'pumpkins' is the winner.
Seega
game

Seega

Age
5 to 18
An ancient game for two from Egypt. You'll need twelve distinctive 'stones' each to play. You could chalk out the board on the ground - do ask permission first.
Alquerque
game

Alquerque

Age
5 to 18
This game for two, was played in ancient Egypt as far back as 1400 BC. The game was taken by the Moors to Spain, where it is mentioned in 13th century manuscripts, and the Spanish name Alquerque derives from the Arabic El- quirkat. Watch out for being 'huffed'.
Introducing NRICH TWILGO
interactivity

Introducing NRICH TWILGO

Age
5 to 18
Challenge level
filled star empty star empty star
We're excited about this new program for drawing beautiful mathematical designs. Can you work out how we made our first few pictures and, even better, share your most elegant solutions with us?
Like a Circle in a Spiral
problem

Like a circle in a spiral

Age
7 to 16
Challenge level
filled star empty star empty star
A cheap and simple toy with lots of mathematics. Can you interpret the images that are produced? Can you predict the pattern that will be produced using different wheels?
Cubic Conundrum
problem

Cubic conundrum

Age
7 to 16
Challenge level
filled star filled star filled star
Which of the following cubes can be made from these nets?
Clocking off
problem

Clocking off

Age
7 to 16
Challenge level
filled star empty star empty star
I found these clocks in the Arts Centre at the University of Warwick intriguing - do they really need four clocks and what times would be ambiguous with only two or three of them?
Fruity Totals
problem

Fruity totals

Age
7 to 16
Challenge level
filled star empty star empty star

In this interactivity each fruit has a hidden value. Can you deduce what each one is worth?

Prime Magic
problem

Prime magic

Age
7 to 16
Challenge level
filled star filled star empty 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?
Air Nets
problem

Air nets

Age
7 to 18
Challenge level
filled star empty star empty star
Can you visualise whether these nets fold up into 3D shapes? Watch the videos each time to see if you were correct.
Searching for mean(ing)
problem

Searching for mean(ing)

Age
11 to 16
Challenge level
filled star filled star empty star

If you have a large supply of 3kg and 8kg weights, how many of each would you need for the average (mean) of the weights to be 6kg?

Sprouts
game

Sprouts

Age
11 to 16
Challenge level
filled star filled star empty star
A game for 2 people. Take turns joining two dots, until your opponent is unable to move.
Cuboid challenge
problem

Cuboid challenge

Age
11 to 16
Challenge level
filled star filled star empty star

What's the largest volume of box you can make from a square of paper?

problem

Marbles in a box

Age
11 to 16
Challenge level
filled star filled star empty star

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

Wipeout
problem

Wipeout

Age
11 to 16
Challenge level
filled star filled star empty star

Can you do a little mathematical detective work to figure out which number has been wiped out?

Instant Insanity
problem

Instant insanity

Age
11 to 18
Challenge level
filled star filled star filled 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.

Hamiltonian Cube
problem

Hamiltonian cube

Age
11 to 16
Challenge level
filled star filled star empty star
Weekly Problem 36 - 2007
Find the length along the shortest path passing through certain points on the cube.
The Triangle Game
game

The triangle game

Age
11 to 16
Challenge level
filled star empty star empty star
Can you discover whether this is a fair game?
Who's who?
problem

Who's who?

Age
11 to 16
Challenge level
filled star filled star empty star

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

Funny Factorisation
problem

Funny factorisation

Age
11 to 16
Challenge level
filled star filled star empty star

Using the digits 1 to 9, the number 4396 can be written as the product of two numbers. Can you find the factors?

Charting success
problem

Charting success

Age
11 to 16
Challenge level
filled star empty star empty star
Can you make sense of the charts and diagrams that are created and used by sports competitors, trainers and statisticians?
Charting more success
problem

Charting more success

Age
11 to 16
Challenge level
filled star empty star empty star
Can you make sense of the charts and diagrams that are created and used by sports competitors, trainers and statisticians?
What is the question?
problem

What is the question?

Age
11 to 16
Challenge level
filled star empty star empty star
These pictures and answers leave the viewer with the problem "What is the Question". Can you give the question and how the answer follows?
The Bridges of Konigsberg
problem

The bridges of Konigsberg

Age
11 to 18
Challenge level
filled star empty star empty star

Investigate how networks can be used to solve a problem for the 18th Century inhabitants of Konigsberg.

Nine Colours
problem

Nine colours

Age
11 to 16
Challenge level
filled star filled star filled 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?

What's it worth?
problem

What's it worth?

Age
11 to 16
Challenge level
filled star empty star empty star

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

11x11 square
problem

11x11 square

Age
11 to 16
Challenge level
filled star filled star empty star
Here's a neat trick you can do with an 11 by 11 square...
Spots and Measles
problem

Spots and measles

Age
11 to 16
Challenge level
filled star filled star empty star

99% of people who have measles have spots. Ben has spots. Do you think he has measles?

Sliding Puzzle
game

Sliding puzzle

Age
11 to 16
Challenge level
filled star empty star empty star
The aim of the game is to slide the green square from the top right hand corner to the bottom left hand corner in the least number of moves.
Vector Racer
game
Favourite

Vector racer

Age
11 to 16
Challenge level
filled star empty star empty star

The classic vector racing game.

LOGO Challenge - Triangles-Squares-Stars
problem

LOGO challenge - triangles-squares-stars

Age
11 to 16
Challenge level
filled star filled star empty star

Can you recreate these designs? What are the basic units? What movement is required between each unit? Some elegant use of procedures will help - variables not essential.

Multiple Surprises
problem

Multiple surprises

Age
11 to 16
Challenge level
filled star empty star empty star

Sequences of multiples keep cropping up...

Ding Dong Bell
article

Ding dong bell

The reader is invited to investigate changes (or permutations) in the ringing of church bells, illustrated by braid diagrams showing the order in which the bells are rung.
Take Three From Five
problem

Take three from five

Age
11 to 16
Challenge level
filled star filled star empty 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?

Placeholder: several colourful numbers
problem

Triangles in the middle

Age
11 to 18
Challenge level
filled star empty star empty star
This task depends on groups working collaboratively, discussing and reasoning to agree a final product.
Pythagoras Proofs
problem

Pythagoras proofs

Age
11 to 16
Challenge level
filled star filled star empty star

Can you make sense of these three proofs of Pythagoras' Theorem?

Charlie's delightful machine
problem

Charlie's delightful machine

Age
11 to 16
Challenge level
filled star empty star empty star

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

Shaping the universe I - planet Earth
article

Shaping the universe I - planet Earth

This article explores ths history of theories about the shape of our planet. It is the first in a series of articles looking at the significance of geometric shapes in the history of astronomy.

Triangle in a Trapezium
problem

Triangle in a trapezium

Age
11 to 16
Challenge level
filled star filled star empty star

Can you find and prove the relationship between the area of a trapezium and the area of a triangle constructed within it?

Yih or Luk tsut k'i or Three Men's Morris
game

Yih or Luk tsut k'i or Three Men's Morris

Age
11 to 18
Challenge level
filled star empty star empty star

Some puzzles requiring no knowledge of knot theory, just a careful inspection of the patterns. A glimpse of the classification of knots and a little about prime knots, crossing numbers and knot arithmetic.

Pyramidal n-gon
problem

Pyramidal n-gon

Age
14 to 16
Challenge level
filled star filled star empty star
The base of a pyramid has n edges. What is the difference between the number of edges the pyramid has and the number of faces the pyramid has?
Always Perfect
problem

Always perfect

Age
14 to 18
Challenge level
filled star filled star empty star

Show that if you add 1 to the product of four consecutive numbers the answer is ALWAYS a perfect square.

Summing squares
problem

Summing squares

Age
14 to 16
Challenge level
filled star filled star empty star
Discover a way to sum square numbers by building cuboids from small cubes. Can you picture how the sequence will grow?
Semicircular Design
problem

Semicircular design

Age
14 to 16
Challenge level
filled star empty star empty star
Weekly Problem 9 - 2016
The diagram to the right shows a logo made from semi-circular arcs. What fraction of the logo is shaded?
problem

Salinon

Age
14 to 16
Challenge level
filled star empty star empty star

This shape comprises four semi-circles. What is the relationship between the area of the shaded region and the area of the circle on AB as diameter?

Curve Hunter
problem

Curve hunter

Age
14 to 18
Challenge level
filled star empty star empty star

This problem challenges you to sketch curves with different properties.

One and three
problem

One and three

Age
14 to 16
Challenge level
filled star filled star empty star
Two motorboats travelling up and down a lake at constant speeds leave opposite ends A and B at the same instant, passing each other, for the first time 600 metres from A, and on their return, 400 metres from B. How long is the lake?
Factorising with Multilink
problem

Factorising with multilink

Age
14 to 16
Challenge level
filled star empty star empty star

Can you find out what is special about the dimensions of rectangles you can make with squares, sticks and units?

A Tilted Square
problem

A tilted square

Age
14 to 16
Challenge level
filled star filled star filled star

The opposite vertices of a square have coordinates (a,b) and (c,d). What are the coordinates of the other vertices?

A question of scale
problem

A question of scale

Age
14 to 16
Challenge level
filled star filled star empty star

Use your skill and knowledge to place various scientific lengths in order of size. Can you judge the length of objects with sizes ranging from 1 Angstrom to 1 million km with no wrong attempts?

In or Out?
problem

In or out?

Age
14 to 16
Challenge level
filled star filled star filled star
Weekly Problem 52 - 2014
Four arcs are drawn in a circle to create a shaded area. What fraction of the area of the circle is shaded?
problem

Triangles and petals

Age
14 to 16
Challenge level
filled star filled star empty star

An equilateral triangle rotates around regular polygons and produces an outline like a flower. What are the perimeters of the different flowers?

Travelling by Train
problem

Travelling by train

Age
14 to 16
Challenge level
filled star filled star empty star
Stephen stops at Darlington on his way to Durham. At what time does he arrive at Durham?
Platonic Planet
problem

Platonic planet

Age
14 to 16
Challenge level
filled star filled star filled star
Glarsynost lives on a planet whose shape is that of a perfect regular dodecahedron. Can you describe the shortest journey she can make to ensure that she will see every part of the planet?
Sliced
problem

Sliced

Age
14 to 16
Challenge level
filled star filled star empty star
An irregular tetrahedron has two opposite sides the same length a and the line joining their midpoints is perpendicular to these two edges and is of length b. What is the volume of the tetrahedron?
Plus Minus
problem

Plus minus

Age
14 to 16
Challenge level
filled star filled star empty star

Can you explain the surprising results Jo found when she calculated the difference between square numbers?

Nicely Similar
problem

Nicely similar

Age
14 to 16
Challenge level
filled star filled star empty star

If the hypotenuse (base) length is 100cm and if an extra line splits the base into 36cm and 64cm parts, what were the side lengths for the original right-angled triangle?

Fill Me Up Too
problem

Fill me up too

Age
14 to 16
Challenge level
filled star filled star empty star

In Fill Me Up we invited you to sketch graphs as vessels are filled with water. Can you work out the equations of the graphs?

Jam
game

Jam

Age
14 to 16
Challenge level
filled star filled star filled star
A game for 2 players
Overlap
problem

Overlap

Age
14 to 16
Challenge level
filled star filled star empty star

A red square and a blue square overlap. Is the area of the overlap always the same?

Trisected Triangle
problem

Trisected triangle

Age
14 to 16
Challenge level
filled star filled star empty star
Weekly Problem 34 - 2015
Four tiles are given. For which of them can three be placed together to form an equilateral triangle?
Pair Products
problem

Pair products

Age
14 to 16
Challenge level
filled star empty star empty star

Choose four consecutive whole numbers. Multiply the first and last numbers together. Multiply the middle pair together. What do you notice?

Oldest and Youngest
problem

Oldest and youngest

Age
14 to 16
Challenge level
filled star filled star empty star
Edith had 9 children at 15 month intervals. If the oldest is now six times as old as the youngest, how old is her youngest child?
Circuit training
problem

Circuit training

Age
14 to 16
Challenge level
filled star empty star empty star
Mike and Monisha meet at the race track, which is 400m round. Just to make a point, Mike runs anticlockwise whilst Monisha runs clockwise. Where will they meet on their way around and will they ever meet at the start again? If so, after how many circuits?
Sitting Pretty
problem

Sitting pretty

Age
14 to 16
Challenge level
filled star filled star empty star

A circle of radius r touches two sides of a right angled triangle, sides x and y, and has its centre on the hypotenuse. Can you prove the formula linking x, y and r?

Dating made Easier
problem

Dating made easier

Age
14 to 16
Challenge level
filled star filled star filled star

If a sum invested gains 10% each year how long before it has doubled its value?

Spotting the loophole
problem

Spotting the loophole

Age
14 to 16
Challenge level
filled star empty star empty star

A visualisation problem in which you search for vectors which sum to zero from a jumble of arrows. Will your eyes be quicker than algebra?

What's that graph?
problem

What's that graph?

Age
14 to 18
Challenge level
filled star filled star empty star

Can you work out which processes are represented by the graphs?

Jam
game

Jam

Age
14 to 16
Challenge level
filled star filled star filled star

To avoid losing think of another very well known game where the patterns of play are similar.

problem

Immersion

Age
14 to 16
Challenge level
filled star filled star empty star

Various solids are lowered into a beaker of water. How does the water level rise in each case?

Perception versus reality
problem

Perception versus reality

Age
14 to 18
Challenge level
filled star empty star empty star

Infographics are a powerful way of communicating statistical information. Can you come up with your own?

Just rolling round
problem

Just rolling round

Age
14 to 16
Challenge level
filled star filled star filled star
P is a point on the circumference of a circle radius r which rolls, without slipping, inside a circle of radius 2r. What is the locus of P?
Perfectly Square
problem

Perfectly square

Age
14 to 16
Challenge level
filled star filled star empty star

The sums of the squares of three related numbers is also a perfect square - can you explain why?

Travelator
problem

Travelator

Age
14 to 16
Challenge level
filled star filled star empty star
When Andrew arrives at the end of the walkway, how far is he ahead of Bill?
Three cubes
problem

Three cubes

Age
14 to 16
Challenge level
filled star filled star empty star

Can you work out the dimensions of the three cubes?

Something in Common
problem

Something in common

Age
14 to 16
Challenge level
filled star filled star filled star
A square of area 3 square units cannot be drawn on a 2D grid so that each of its vertices have integer coordinates, but can it be drawn on a 3D grid? Investigate squares that can be drawn.
Facial Sums
problem

Facial sums

Age
14 to 16
Challenge level
filled star filled star empty star
Can you make the numbers around each face of this solid add up to the same total?
Gutter
problem

Gutter

Age
14 to 16
Challenge level
filled star filled star empty star

Manufacturers need to minimise the amount of material used to make their product. What is the best cross-section for a gutter?

Making Tracks
problem

Making tracks

Age
14 to 16
Challenge level
filled star filled star empty star
A bicycle passes along a path and leaves some tracks. Is it possible to say which track was made by the front wheel and which by the back wheel?
Filling the gaps
problem

Filling the gaps

Age
14 to 16
Challenge level
filled star filled star empty star

Which numbers can we write as a sum of square numbers?

Wari
game

Wari

Age
14 to 16
Challenge level
filled star filled star empty star
This is a simple version of an ancient game played all over the world. It is also called Mancala. What tactics will increase your chances of winning?
problem

At right angles

Age
14 to 16
Challenge level
filled star filled star empty star

Can you decide whether two lines are perpendicular or not? Can you do this without drawing them?

Coke machine
problem

Coke machine

Age
14 to 16
Challenge level
filled star empty star empty star
The coke machine in college takes 50 pence pieces. It also takes a certain foreign coin of traditional design...
Changing Places
problem

Changing places

Age
14 to 16
Challenge level
filled star empty star empty star
Place a red counter in the top left corner of a 4x4 array, which is covered by 14 other smaller counters, leaving a gap in the bottom right hand corner (HOME). What is the smallest number of moves it will take to move the red counter to HOME?
Tennis Training
problem

Tennis training

Age
14 to 16
Challenge level
filled star filled star empty star
After tennis training, Andy, Roger and Maria collect up the balls. Can you work out how many Andy collects?
3D Treasure Hunt
problem

3D treasure hunt

Age
14 to 18
Challenge level
filled star filled star empty star

Some treasure has been hidden in a three-dimensional grid! Can you work out a strategy to find it as efficiently as possible?

Centre Square
problem

Centre square

Age
14 to 16
Challenge level
filled star filled star filled star
What does Pythagoras' Theorem tell you about the radius of these circles?
One Out One Under
problem

One out one under

Age
14 to 16
Challenge level
filled star filled star filled star
Imagine a stack of numbered cards with one on top. Discard the top, put the next card to the bottom and repeat continuously. Can you predict the last card?
Which list is which?
problem

Which list is which?

Age
14 to 16
Challenge level
filled star filled star empty star

Six samples were taken from two distributions but they got muddled up. Can you work out which list is which?

Attractive Tablecloths
problem

Attractive tablecloths

Age
14 to 16
Challenge level
filled star filled star empty star

Charlie likes tablecloths that use as many colours as possible, but insists that his tablecloths have some symmetry. Can you work out how many colours he needs for different tablecloth designs?

Curvy areas
problem

Curvy areas

Age
14 to 16
Challenge level
filled star empty star empty star

Have a go at creating these images based on circles. What do you notice about the areas of the different sections?

Box plot match
problem

Box plot match

Age
14 to 16
Challenge level
filled star empty star empty star

Match the cumulative frequency curves with their corresponding box plots.

Just Opposite
problem

Just opposite

Age
14 to 16
Challenge level
filled star filled star empty star
A and C are the opposite vertices of a square ABCD, and have coordinates (a,b) and (c,d), respectively. What are the coordinates of the vertices B and D? What is the area of the square?
Painted Cube
problem

Painted cube

Age
14 to 16
Challenge level
filled star filled star empty star

Imagine a large cube made from small red cubes being dropped into a pot of yellow paint. How many of the small cubes will have yellow paint on their faces?

Mystic Rose
problem

Mystic rose

Age
14 to 16
Challenge level
filled star filled star empty star

Use the animation to help you work out how many lines are needed to draw mystic roses of different sizes.

Slippage
problem

Slippage

Age
14 to 16
Challenge level
filled star filled star empty star
A ladder 3m long rests against a wall with one end a short distance from its base. Between the wall and the base of a ladder is a garden storage box 1m tall and 1m high. What is the maximum distance up the wall which the ladder can reach?
Folding in Half
problem

Folding in half

Age
14 to 16
Challenge level
filled star filled star empty star
How does the perimeter change when we fold this isosceles triangle in half?