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?
Fruity Totals
problem

Fruity totals

Age
7 to 16
Challenge level
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In this interactivity each fruit has a hidden value. Can you deduce what each one is worth?

Air Nets
problem

Air nets

Age
7 to 18
Challenge level
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Can you visualise whether these nets fold up into 3D shapes? Watch the videos each time to see if you were correct.
Clocking off
problem

Clocking off

Age
7 to 16
Challenge level
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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?
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?
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?
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.

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?
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?

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?

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?
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?
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...
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?
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.

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?
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.
Multiple Surprises
problem

Multiple surprises

Age
11 to 16
Challenge level
filled star empty star empty star
Sequences of multiples keep cropping up...
Take Three From Five
problem

Take three from five

Age
11 to 16
Challenge level
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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?

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?
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.
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?

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.
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?

What is the question?
problem

What is the question?

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

Marbles in a box
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?

The Bridges of Konigsberg
problem

The bridges of Konigsberg

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

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.

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?

Placeholder: several colourful numbers
problem

Triangles in the middle

Age
11 to 18
Challenge level
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This task depends on groups working collaboratively, discussing and reasoning to agree a final product.
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.
Back fitter
problem

Back fitter

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

10 graphs of experimental data are given. Can you use a spreadsheet to find algebraic graphs which match them closely, and thus discover the formulae most likely to govern the underlying processes?

Can you traverse it?
problem

Can you traverse it?

Age
14 to 18
Challenge level
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How can you decide if a graph is traversable?

All Tied Up
problem

All tied up

Age
14 to 16
Challenge level
filled star filled star empty star
A ribbon runs around a box so that it makes a complete loop with two parallel pieces of ribbon on the top. How long will the ribbon be?
Cubic Covering
problem

Cubic covering

Age
14 to 16
Challenge level
filled star filled star empty star
A blue cube has blue cubes glued on all of its faces. Yellow cubes are then glued onto all the visible blue facces. How many yellow cubes are needed?
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?

Quadratic Patterns
problem

Quadratic patterns

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

Surprising numerical patterns can be explained using algebra and diagrams...

Jam
game

Jam

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

Surprising transformations

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

I took the graph y=4x+7 and performed four transformations. Can you find the order in which I could have carried out the transformations?

Vanishing point
problem

Vanishing point

Age
14 to 18
Challenge level
filled star filled star empty star
How can visual patterns be used to prove sums of series?
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?
Out of the Window
problem

Out of the window

Age
14 to 16
Challenge level
filled star empty star empty star
Find out how many pieces of hardboard of differing sizes can fit through a rectangular window.
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?
Around and Back
problem

Around and back

Age
14 to 16
Challenge level
filled star filled star filled star
A cyclist and a runner start off simultaneously around a race track each going at a constant speed. The cyclist goes all the way around and then catches up with the runner. He then instantly turns around and heads back to the starting point where he meets the runner who is just finishing his first circuit. Find the ratio of their speeds.
Efficient packing
problem

Efficient packing

Age
14 to 16
Challenge level
filled star empty star empty star
How efficiently can you pack together disks?
Pythagoras Perimeters
problem

Pythagoras perimeters

Age
14 to 16
Challenge level
filled star filled star empty star
If you know the perimeter of a right angled triangle, what can you say about the area?
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.

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...
Bike Shop
problem

Bike shop

Age
14 to 16
Challenge level
filled star filled star empty star
If I walk to the bike shop, but then cycle back, what is my average speed?
Triangle midpoints
problem

Triangle midpoints

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

You are only given the three midpoints of the sides of a triangle. How can you construct the original triangle?

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?

Packing 3D shapes
problem

Packing 3D shapes

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

What 3D shapes occur in nature. How efficiently can you pack these shapes together?

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?
Vector walk
problem

Vector walk

Age
14 to 18
Challenge level
filled star empty star empty star
Starting with two basic vector steps, which destinations can you reach on a vector walk?
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?
Bus Stop
problem

Bus stop

Age
14 to 16
Challenge level
filled star filled star filled star
Two buses leave at the same time from two towns Shipton and Veston on the same long road, travelling towards each other. At each mile along the road are milestones. The buses' speeds are constant and in the ratio 5 to 4. The buses travel to and fro between the towns. What milestones are at Shipton and Veston?
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.

Doesn't add up
problem

Doesn't add up

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

In this problem we are faced with an apparently easy area problem, but it has gone horribly wrong! What happened?

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?
AMGM
problem

AMGM

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

Can you use the diagram to prove the AM-GM inequality?

Quadratic Matching
problem

Quadratic matching

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

Can you match each graph to one of the statements?

Terminology
problem

Terminology

Age
14 to 16
Challenge level
filled star filled star empty star
Given an equilateral triangle inside an isosceles triangle, can you find a relationship between the angles?
Building Tetrahedra
problem

Building tetrahedra

Age
14 to 16
Challenge level
filled star filled star empty star
Can you make a tetrahedron whose faces all have the same perimeter?
Inside Out
problem

Inside out

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

There are 27 small cubes in a 3 x 3 x 3 cube, 54 faces being visible at any one time. Is it possible to reorganise these cubes so that by dipping the large cube into a pot of paint three times you can colour every face of all of the smaller cubes?

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?
Fermat's Poser
problem

Fermat's poser

Age
14 to 16
Challenge level
filled star filled star filled star
Find the point whose sum of distances from the vertices (corners) of a given triangle is a minimum.
Steel Cables
problem

Steel cables

Age
14 to 16
Challenge level
filled star empty star empty star
Some students have been working out the number of strands needed for different sizes of cable. Can you make sense of their solutions?
Gnomon dimensions
problem

Gnomon dimensions

Age
14 to 16
Challenge level
filled star filled star empty star
These gnomons appear to have more than a passing connection with the Fibonacci sequence. This problem ask you to investigate some of these connections.
Partly Circles
problem

Partly circles

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

What is the same and what is different about these circle questions? What connections can you make?

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?
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?
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?
A Problem of time
problem

A problem of time

Age
14 to 16
Challenge level
filled star filled star filled star
Consider a watch face which has identical hands and identical marks for the hours. It is opposite to a mirror. When is the time as read direct and in the mirror exactly the same between 6 and 7?
Rectangle Rearrangement
problem

Rectangle rearrangement

Age
14 to 16
Challenge level
filled star empty star empty star
A 3x8 rectangle is cut into two pieces... then rearranged to form a right-angled triangle. What is the perimeter of the triangle formed?
Summing geometric progressions
problem

Summing geometric progressions

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

Watch the video to see how to sum the sequence. Can you adapt the method to sum other sequences?

Square Number Surprises
problem

Square number surprises

Age
14 to 16
Challenge level
filled star filled star empty star
There are unexpected discoveries to be made about square numbers...
Pick's Theorem
problem

Pick's theorem

Age
14 to 16
Challenge level
filled star filled star empty star
Polygons drawn on square dotty paper have dots on their perimeter (p) and often internal (i) ones as well. Find a relationship between p, i and the area of the polygons.
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?
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?
Hypotenuse Lattice points
problem

Hypotenuse lattice points

Age
14 to 16
Challenge level
filled star filled star filled star
The triangle OMN has vertices on the axes with whole number co-ordinates. How many points with whole number coordinates are there on the hypotenuse MN?
Iff
problem

Iff

Age
14 to 18
Challenge level
filled star filled star empty star
Take a triangular number, multiply it by 8 and add 1. What is special about your answer? Can you prove it?
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?
Puzzling Place Value
problem

Puzzling place value

Age
14 to 16
Challenge level
filled star filled star empty star
Can you explain what is going on in these puzzling number tricks?
Corridors
problem

Corridors

Age
14 to 16
Challenge level
filled star filled star empty star
A 10x10x10 cube is made from 27 2x2 cubes with corridors between them. Find the shortest route from one corner to the opposite corner.
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.
Packing Boxes
problem

Packing boxes

Age
14 to 16
Challenge level
filled star filled star empty star
Look at the times that Harry, Christine and Betty take to pack boxes when working in pairs, to find how fast Christine can pack boxes by herself.
Star Gazing
problem

Star gazing

Age
14 to 16
Challenge level
filled star empty star empty star
Find the ratio of the outer shaded area to the inner area for a six pointed star and an eight pointed star.
Double Trouble
problem

Double trouble

Age
14 to 16
Challenge level
filled star empty star empty star
Simple additions can lead to intriguing results...
Tetra Square
problem

Tetra square

Age
14 to 18
Challenge level
filled star filled star empty star
ABCD is a regular tetrahedron and the points P, Q, R and S are the midpoints of the edges AB, BD, CD and CA. Prove that PQRS is a square.
Hollow Squares
problem

Hollow squares

Age
14 to 16
Challenge level
filled star empty star empty star
Which armies can be arranged in hollow square fighting formations?