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?
Move just three of the circles so that the triangle faces in the opposite direction.
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?
What is the greatest number of squares you can make by overlapping three squares?
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.
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.
What happens when you turn these cogs? Investigate the differences between turning two cogs of different sizes and two cogs which are the same.
Use your mouse to move the red and green parts of this disc. Can you make images which show the turnings described?
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?
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?
Can you work out what is wrong with the cogs on a UK 2 pound coin?
A game for 1 or 2 people. Use the interactive version, or play with friends. Try to round up as many counters as possible.
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!
Seeing Squares game for an adult and child. Can you come up with a way of always winning this game?
Use the interactivity to help get a feel for this problem and to find out all the possible ways the balls could land.
Use the interactivity to find all the different right-angled triangles you can make by just moving one corner of the starting triangle.
Investigate how the four L-shapes fit together to make an enlarged L-shape. You could explore this idea with other shapes too.
How many triangles can you make using sticks that are 3cm, 4cm and 5cm long?
If you can post the triangle with either the blue or yellow colour face up, how many ways can it be posted altogether?
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?
Take it in turns to make a triangle on the pegboard. Can you block your opponent?
Can you find all the different triangles on these peg boards, and find their angles?
There are nine teddies in Teddy Town - three red, three blue and three yellow. There are also nine houses, three of each colour. Can you put them on the map of Teddy Town according to the rules?
How many trains can you make which are the same length as Matt's and Katie's, using rods that are identical?
Place the numbers 1 to 10 in the circles so that each number is the difference between the two numbers just below it.
Place the numbers 1 to 6 in the circles so that each number is the difference between the two numbers just below it.
Find out how we can describe the "symmetries" of this triangle and investigate some combinations of rotating and flipping it.
Place six toy ladybirds into the box so that there are two ladybirds in every column and every row.
Terry and Ali are playing a game with three balls. Is it fair that Terry wins when the middle ball is red?
Three beads are threaded on a circular wire and are coloured either red or blue. Can you find all four different combinations?
Imagine a wheel with different markings painted on it at regular intervals. Can you predict the colour of the 18th mark? The 100th mark?
Here are some rods that are different colours. How could I make a yellow rod using white and red rods?
How many different triangles can you make on a circular pegboard that has nine pegs?
Use the clues to colour each square.
Take it in turns to place a domino on the grid. One to be placed horizontally and the other vertically. Can you make it impossible for your opponent to play?
Have a go at this well-known challenge. Can you swap the frogs and toads in as few slides and jumps as possible?
Can you put the numbers 1 to 8 into the circles so that the four calculations are correct?
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.
Can you put the numbers from 1 to 15 on the circles so that no consecutive numbers lie anywhere along a continuous straight line?
Board Block game for two. Can you stop your partner from being able to make a shape on the board?
What do the numbers shaded in blue on this hundred square have in common? What do you notice about the pink numbers? How about the shaded numbers in the other squares?
First Connect Three game for an adult and child. Use the dice numbers and either addition or subtraction to get three numbers in a straight line.
Investigate the smallest number of moves it takes to turn these mats upside-down if you can only turn exactly three at a time.
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....?
Try out the lottery that is played in a far-away land. What is the chance of winning?
In this activity, the computer chooses a times table and shifts it. Can you work out the table and the shift each time?
Arrange any number of counters from these 18 on the grid to make a rectangle. What numbers of counters make rectangles? How many different rectangles can you make with each number of counters?
A game in which players take it in turns to choose a number. Can you block your opponent?