Six circles around a central circle make a flower. Watch the flower
as you change the radii in this circle packing. Prove that with the
given ratios of the radii the petals touch and fit perfectly.
This is an interactivity in which you have to sort into the correct
order the steps in the proof of the formula for the sum of a
Can you beat the computer in the challenging strategy game?
Make and prove a conjecture about the cyclic quadrilateral
inscribed in a circle of radius r that has the maximum perimeter and the maximum area.
Find the vertices of a pentagon given the midpoints of its sides.
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.
A point P is selected anywhere inside an equilateral triangle. What
can you say about the sum of the perpendicular distances from P to
the sides of the triangle? Can you prove your conjecture?
Can you make a right-angled triangle on this peg-board by joining
up three points round the edge?
This resource contains interactive problems to support work on
number sequences at Key Stage 4.
Discover a handy way to describe reorderings and solve our anagram
in the process.
An environment that enables you to investigate tessellations of
Can you locate these values on this interactive logarithmic scale?
Match pairs of cards so that they have equivalent ratios.
Can you work through these direct proofs, using our interactive
A mathematically themed crossword.
This resource contains a range of problems and interactivities on
the theme of coordinates in two and three dimensions.
How good are you at finding the formula for a number pattern ?
The interactive diagram has two labelled points, A and B. It is
designed to be used with the problem "Cushion Ball"
Re-arrange the pieces of the puzzle to form a rectangle and then to
form an equilateral triangle. Calculate the angles and lengths.
Use Excel to explore multiplication of fractions.
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?
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. . . .
If you continue the pattern, can you predict what each of the following areas will be? Try to explain your prediction.
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?
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. . . .
A spherical balloon lies inside a wire frame. How much do you need
to deflate it to remove it from the frame if it remains a sphere?
Can you give the coordinates of the vertices of the fifth point in
the patterm on this 3D grid?
Cellular is an animation that helps you make geometric sequences composed of square cells.
This set of resources for teachers offers interactive environments
to support work on loci at Key Stage 4.
Match the cards of the same value.
A metal puzzle which led to some mathematical questions.
How can we solve equations like 13x + 29y = 42 or 2x +4y = 13 with
the solutions x and y being integers? Read this article to find
Try this interactivity to familiarise yourself with the proof that the square root of 2 is irrational. Sort the steps of the proof into the correct order.
An environment that simulates a protractor carrying a right- angled
triangle of unit hypotenuse.
A weekly challenge concerning prime numbers.
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 Excel to practise adding and subtracting fractions.
An Excel spreadsheet with an investigation.
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
Play countdown with matrices
Take any parallelogram and draw squares on the sides of the
parallelogram. What can you prove about the quadrilateral formed by
joining the centres of these squares?
Use an Excel to investigate division. Explore the relationships
between the process elements using an interactive spreadsheet.
Square It game for an adult and child. Can you come up with a way of always winning this game?
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. . . .
The classic vector racing game brought to a screen near you.
Here is a chance to play a fractions version of the classic
Use an interactive Excel spreadsheet to investigate factors and
This game challenges you to locate hidden triangles in The White
Box by firing rays and observing where the rays exit the Box.
Help the bee to build a stack of blocks far enough to save his
friend trapped in the tower.