Show that for any triangle it is always possible to construct 3 touching circles with centres at the vertices. Is it possible to construct touching circles centred at the vertices of any polygon?

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

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.

Can you beat the computer in the challenging strategy game?

A collection of resources to support work on Factors and Multiples at Secondary level.

Help the bee to build a stack of blocks far enough to save his friend trapped in the tower.

Use an interactive Excel spreadsheet to explore number in this exciting game!

Triangle ABC has equilateral triangles drawn on its edges. Points P, Q and R are the centres of the equilateral triangles. What can you prove about the triangle PQR?

A group of interactive resources to support work on percentages Key Stage 4.

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

Use Excel to investigate the effect of translations around a number grid.

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.

If you continue the pattern, can you predict what each of the following areas will be? Try to explain your prediction.

Match pairs of cards so that they have equivalent ratios.

An environment that enables you to investigate tessellations of regular polygons

The interactive diagram has two labelled points, A and B. It is designed to be used with the problem "Cushion Ball"

This is an interactivity in which you have to sort the steps in the completion of the square into the correct order to prove the formula for the solutions of quadratic equations.

Start with any number of counters in any number of piles. 2 players take it in turns to remove any number of counters from a single pile. The winner is the player to take the last counter.

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?

Discover a handy way to describe reorderings and solve our anagram in the process.

Use an Excel spreadsheet to explore long multiplication.

A simple file for the Interactive whiteboard or PC screen, demonstrating equivalent fractions.

This game challenges you to locate hidden triangles in The White Box by firing rays and observing where the rays exit the Box.

Use Excel to explore multiplication of fractions.

A simple spinner that is equally likely to land on Red or Black. Useful if tossing a coin, dropping it, and rummaging about on the floor have lost their appeal. Needs a modern browser; if IE then at. . . .

An environment that simulates a protractor carrying a right- angled triangle of unit hypotenuse.

A tool for generating random integers.

A collection of our favourite pictorial problems, one for each day of Advent.

Use an Excel to investigate division. Explore the relationships between the process elements using an interactive spreadsheet.

Cellular is an animation that helps you make geometric sequences composed of square cells.

Here is a chance to play a fractions version of the classic Countdown Game.

This set of resources for teachers offers interactive environments to support work on loci at Key Stage 4.

A metal puzzle which led to some mathematical questions.

A java applet that takes you through the steps needed to solve a Diophantine equation of the form Px+Qy=1 using Euclid's algorithm.

Use an interactive Excel spreadsheet to investigate factors and multiples.

Can you give the coordinates of the vertices of the fifth point in the patterm on this 3D grid?

Use Excel to practise adding and subtracting fractions.

Match the cards of the same value.

A right-angled isosceles triangle is rotated about the centre point of a square. What can you say about the area of the part of the square covered by the triangle as it rotates?

The classic vector racing game brought to a screen near you.

An Excel spreadsheet with an investigation.

Can you beat Piggy in this simple dice game? Can you figure out Piggy's strategy, and is there a better one?

These formulae are often quoted, but rarely proved. In this article, we derive the formulae for the volumes of a square-based pyramid and a cone, using relatively simple mathematical concepts.

Slide the pieces to move Khun Phaen past all the guards into the position on the right from which he can escape to freedom.

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. . . .

Do you know how to find the area of a triangle? You can count the squares. What happens if we turn the triangle on end? Press the button and see. Try counting the number of units in the triangle now. . . .

A game for 2 players. Can be played online. One player has 1 red counter, the other has 4 blue. The red counter needs to reach the other side, and the blue needs to trap the red.

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?