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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

Visualising

Visualising is part of our Working Mathematically collection.

Treasure Hunt

Age 7 to 14
Challenge Level Yellow star

Can you find a reliable strategy for choosing coordinates that will locate the treasure in the minimum number of guesses?

Hidden Squares

Age 11 to 14
Challenge Level Yellow star

Can you find the squares hidden on these coordinate grids?

Isosceles Triangles

Age 11 to 14
Challenge Level Yellow star

Draw some isosceles triangles with an area of $9$cm$^2$ and a vertex at (20,20). If all the vertices must have whole number coordinates, how many is it possible to draw?

Picturing Triangular Numbers

Age 11 to 14
Challenge Level Yellow star

Triangular numbers can be represented by a triangular array of squares. What do you notice about the sum of identical triangle numbers?

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?

Picturing Square Numbers

Age 11 to 14
Challenge Level Yellow star

Square numbers can be represented as the sum of consecutive odd numbers. What is the sum of 1 + 3 + ..... + 149 + 151 + 153?

Polygon Rings

Age 11 to 14
Challenge Level Yellow star

Join pentagons together edge to edge. Will they form a ring?

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?

Polygon Pictures

Age 11 to 14
Challenge Level Yellow star

Can you work out how these polygon pictures were drawn, and use that to figure out their angles?

Shady Symmetry

Age 11 to 14
Challenge Level Yellow star

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

Constructing Triangles

Age 11 to 14
Challenge Level Yellow star

Generate three random numbers to determine the side lengths of a triangle. What triangles can you draw?

Fence It

Age 11 to 14
Challenge Level Yellow star

If you have only 40 metres of fencing available, what is the maximum area of land you can fence off?

Diminishing Returns

Age 11 to 14
Challenge Level Yellow star

How much of the square is coloured blue? How will the pattern continue?

An Unusual Shape

Age 11 to 14
Challenge Level Yellow starYellow star

Can you maximise the area available to a grazing goat?

Quadrilaterals in a Square

Age 11 to 14
Challenge Level Yellow starYellow star

What's special about the area of quadrilaterals drawn in a square?

Square Coordinates

Age 11 to 14
Challenge Level Yellow starYellow star

A tilted square is a square with no horizontal sides. Can you devise a general instruction for the construction of a square when you are given just one of its sides?

On the Edge

Age 11 to 14
Challenge Level Yellow starYellow star

If you move the tiles around, can you make squares with different coloured edges?

Shear Magic

Age 11 to 14
Challenge Level Yellow starYellow star

Explore the area of families of parallelograms and triangles. Can you find rules to work out the areas?

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?

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.

Seven Squares - Group-worthy Task

Age 11 to 14
Challenge Level Yellow starYellow star

Choose a couple of the sequences. Try to picture how to make the next, and the next, and the next... Can you describe your reasoning?

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?

Coordinate Patterns

Age 11 to 14
Challenge Level Yellow starYellow star

Charlie and Alison have been drawing patterns on coordinate grids. Can you picture where the patterns lead?

The Farmers' Field Boundary

Age 11 to 14
Challenge Level Yellow starYellow star

The farmers want to redraw their field boundary but keep the area the same. Can you advise them?

Rolling Around

Age 11 to 14
Challenge Level Yellow starYellow star

A circle rolls around the outside edge of a square so that its circumference always touches the edge of the square. Can you describe the locus of the centre of the circle?

Seven Squares

Age 11 to 14
Challenge Level Yellow starYellow star

Watch these videos to see how Phoebe, Alice and Luke chose to draw 7 squares. How would they draw 100?

Triangles to Tetrahedra

Age 11 to 14
Challenge Level Yellow starYellow starYellow star

Imagine you have an unlimited number of four types of triangle. How many different tetrahedra can you make?

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?

Efficient Cutting

Age 11 to 14
Challenge Level Yellow starYellow starYellow star

Use a single sheet of A4 paper and make a cylinder having the greatest possible volume. The cylinder must be closed off by a circle at each end.

Visualising - Short Problems

Age 11 to 16

A collection of short Stage 3 and 4 problems on Visualising.

Semi-regular Tessellations

Age 11 to 16
Challenge Level Yellow star

Semi-regular tessellations combine two or more different regular polygons to fill the plane. Can you find all the semi-regular tessellations?

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.

Diamond Collector

Age 11 to 16
Challenge Level Yellow star

Collect as many diamonds as you can by drawing three straight lines.

Parallelogram 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 parallelogram.

Rhombus It

Age 11 to 16
Challenge Level Yellow starYellow 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 rhombus.

Cuboid Challenge

Age 11 to 16
Challenge Level Yellow starYellow star

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

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?

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?

Spotting the Loophole

Age 14 to 16
Challenge Level Yellow 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?

Steel Cables

Age 14 to 16
Challenge Level Yellow star

Some students have been working out the number of strands needed for different sizes of cable. Can you make sense of their solutions?

Speeding Boats

Age 14 to 16
Challenge Level Yellow star

Two boats travel up and down a lake. Can you picture where they will cross if you know how fast each boat is travelling?

Double Trouble

Age 14 to 16
Challenge Level Yellow star

Simple additions can lead to intriguing results...

Picture Story

Age 14 to 16
Challenge Level Yellow starYellow star

Can you see how this picture illustrates the formula for the sum of the first six cube numbers?

Partly Painted Cube

Age 14 to 16
Challenge Level Yellow starYellow star

Jo made a cube from some smaller cubes, painted some of the faces of the large cube, and then took it apart again. 45 small cubes had no paint on them at all. How many small cubes did Jo use?

The Spider and the Fly

Age 14 to 16
Challenge Level Yellow starYellow star

A spider is sitting in the middle of one of the smallest walls in a room and a fly is resting beside the window. What is the shortest distance the spider would have to crawl to catch the fly?

Three Cubes

Age 14 to 16
Challenge Level Yellow starYellow star

Can you work out the dimensions of the three cubes?

Doesn't Add Up

Age 14 to 16
Challenge Level Yellow starYellow star

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

Tied Up

Age 14 to 16
ShortChallenge Level Yellow starYellow star

How much of the field can the animals graze?

Pick's Theorem

Age 14 to 16
Challenge Level Yellow starYellow 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.

Building Tetrahedra

Age 14 to 16
Challenge Level Yellow starYellow star

Can you make a tetrahedron whose faces all have the same perimeter?

Attractive Tablecloths

Age 14 to 16
Challenge Level Yellow starYellow 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?

Mystic Rose

Age 14 to 16
Challenge Level Yellow starYellow star

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

Painted Cube

Age 14 to 16
Challenge Level Yellow starYellow 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?

Bendy Quad

Age 14 to 16
Challenge Level Yellow starYellow starYellow star

Four rods are hinged at their ends to form a convex quadrilateral. Investigate the different shapes that the quadrilateral can take. Be patient this problem may be slow to load.

Vector Journeys

Age 14 to 18
Challenge Level Yellow star

Charlie likes to go for walks around a square park, while Alison likes to cut across diagonally. Can you find relationships between the vectors they walk along?

Circles Ad Infinitum

Age 16 to 18
Challenge Level Yellow starYellow star

A circle is inscribed in an equilateral triangle. Smaller circles touch it and the sides of the triangle, the process continuing indefinitely. What is the sum of the areas of all the circles?

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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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