Place the numbers 1 to 10 in the circles so that each number is the difference between the two numbers just below it.
Can you put the numbers 1 to 8 into the circles so that the four calculations are correct?
Place six toy ladybirds into the box so that there are two ladybirds in every column and every row.
What happens when you try and fit the triomino pieces into these two grids?
Can you see why 2 by 2 could be 5? Can you predict what 2 by 10 will be?
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?
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?
Place the numbers 1 to 6 in the circles so that each number is the difference between the two numbers just below it.
Use the clues to colour each square.
Choose a symbol to put into the number sentence.
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?
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.
Use your mouse to move the red and green parts of this disc. Can you make images which show the turnings described?
How many triangles can you make using sticks that are 3cm, 4cm and 5cm long?
Imagine a wheel with different markings painted on it at regular intervals. Can you predict the colour of the 18th mark? The 100th mark?
Three beads are threaded on a circular wire and are coloured either red or blue. Can you find all four different combinations?
Here are some rods that are different colours. How could I make a yellow rod using white and red rods?
Use the interactivity to help get a feel for this problem and to find out all the possible ways the balls could land.
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?
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?
How many trains can you make which are the same length as Matt's and Katie's, using rods that are identical?
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?
Take it in turns to make a triangle on the pegboard. Can you block your opponent?
Sort the houses in my street into different groups. Can you do it in any other ways?
How many different triangles can you make on a circular pegboard that has nine pegs?
Use the interactivity to find all the different right-angled triangles you can make by just moving one corner of the starting triangle.
Use the interactivity to investigate what kinds of triangles can be drawn on peg boards with different numbers of pegs.
This 100 square jigsaw is written in code. It starts with 1 and ends with 100. Can you build it up?
Have a go at this well-known challenge. Can you swap the frogs and toads in as few slides and jumps as possible?
How many different triangles can you draw on the dotty grid which each have one dot in the middle?
In this activity, the computer chooses a times table and shifts it. Can you work out the table and the shift each time?
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?
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....?
Can you find a reliable strategy for choosing coordinates that will locate the treasure in the minimum number of guesses?
There are three versions of this challenge. The idea is to change the colour of all the spots on the grid. Can you do it in fewer throws of the dice?
Here is a chance to play a version of the classic Countdown Game.
Try to stop your opponent from being able to split the piles of counters into unequal numbers. Can you find a strategy?
Calculate the fractional amounts of money to match pairs of cards with the same value.
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?
Train game for an adult and child. Who will be the first to make the train?
A game for 2 players that can be played online. Players take it in turns to select a word from the 9 words given. The aim is to select all the occurrences of the same letter.
A game for 1 or 2 people. Use the interactive version, or play with friends. Try to round up as many counters as possible.
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.
A game to be played against the computer, or in groups. Pick a 7-digit number. A random digit is generated. What must you subract to remove the digit from your number? the first to zero wins.
An interactive game for 1 person. You are given a rectangle with 50 squares on it. Roll the dice to get a percentage between 2 and 100. How many squares is this? Keep going until you get 100. . . .
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.
An interactive activity for one to experiment with a tricky tessellation
Terry and Ali are playing a game with three balls. Is it fair that Terry wins when the middle ball is red?