How many different triangles can you make on a circular pegboard that has nine pegs?

Cut four triangles from a square as shown in the picture. How many different shapes can you make by fitting the four triangles back together?

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.

Use your mouse to move the red and green parts of this disc. Can you make images which show the turnings described?

Use the interactivity to find all the different right-angled triangles you can make by just moving one corner of the starting triangle.

This was a problem for our birthday website. Can you use four of these pieces to form a square? How about making a square with all five pieces?

Can you sort these triangles into three different families and explain how you did it?

How many different triangles can you draw on the dotty grid which each have one dot in the middle?

Sort the houses in my street into different groups. Can you do it in any other ways?

If you can post the triangle with either the blue or yellow colour face up, how many ways can it be posted altogether?

Board Block game for two. Can you stop your partner from being able to make a shape on the board?

What is the greatest number of squares you can make by overlapping three squares?

Can you find all the different triangles on these peg boards, and find their angles?

Use the interactivity to investigate what kinds of triangles can be drawn on peg boards with different numbers of pegs.

Take it in turns to make a triangle on the pegboard. Can you block your opponent?

The computer has made a rectangle and will tell you the number of spots it uses in total. Can you find out where the rectangle is?

Find out what a "fault-free" rectangle is and try to make some of your own.

A game for 1 or 2 people. Use the interactive version, or play with friends. Try to round up as many counters as possible.

Investigate how the four L-shapes fit together to make an enlarged L-shape. You could explore this idea with other shapes too.

How can the same pieces of the tangram make this bowl before and after it was chipped? Use the interactivity to try and work out what is going on!

Choose the size of your pegboard and the shapes you can make. Can you work out the strategies needed to block your opponent?

This 100 square jigsaw is written in code. It starts with 1 and ends with 100. Can you build it up?

Explore this interactivity and see if you can work out what it does. Could you use it to estimate the area of a shape?

Hover your mouse over the counters to see which ones will be removed. Click to remove them. The winner is the last one to remove a counter. How you can make sure you win?

Use the interactivity to find out how many quarter turns the man must rotate through to look like each of the pictures.

How many different ways can you find to join three equilateral triangles together? Can you convince us that you have found them all?

Investigate the smallest number of moves it takes to turn these mats upside-down if you can only turn exactly three at a time.

You have 4 red and 5 blue counters. How many ways can they be placed on a 3 by 3 grid so that all the rows columns and diagonals have an even number of red counters?

What happens when you turn these cogs? Investigate the differences between turning two cogs of different sizes and two cogs which are the same.

Can you work out what is wrong with the cogs on a UK 2 pound coin?

What shape is the overlap when you slide one of these shapes half way across another? Can you picture it in your head? Use the interactivity to check your visualisation.

How many triangles can you make using sticks that are 3cm, 4cm and 5cm long?

What does the overlap of these two shapes look like? Try picturing it in your head and then use the interactivity to test your prediction.

Seeing Squares game for an adult and child. Can you come up with a way of always winning this game?

A tetromino is made up of four squares joined edge to edge. Can this tetromino, together with 15 copies of itself, be used to cover an eight by eight chessboard?

What happens when you try and fit the triomino pieces into these two grids?

Place the numbers 1 to 6 in the circles so that each number is the difference between the two numbers just below it.

Can you see why 2 by 2 could be 5? Can you predict what 2 by 10 will be?

Here are some rods that are different colours. How could I make a dark green rod using yellow and white rods?

Terry and Ali are playing a game with three balls. Is it fair that Terry wins when the middle ball is red?

Place the numbers 1 to 10 in the circles so that each number is the difference between the two numbers just below it.

Three beads are threaded on a circular wire and are coloured either red or blue. Can you find all four different combinations?

Is it possible to place 2 counters on the 3 by 3 grid so that there is an even number of counters in every row and every column? How about if you have 3 counters or 4 counters or....?

This problem is based on a code using two different prime numbers less than 10. You'll need to multiply them together and shift the alphabet forwards by the result. Can you decipher the code?

What shaped overlaps can you make with two circles which are the same size? What shapes are 'left over'? What shapes can you make when the circles are different sizes?

Can you make a train the same length as Laura's but using three differently coloured rods? Is there only one way of doing it?

How many trains can you make which are the same length as Matt's, using rods that are identical?

A game for 1 person. Can you work out how the dice must be rolled from the start position to the finish? Play on line.