Starting with the number 180, take away 9 again and again, joining up the dots as you go. Watch out - don't join all the dots!
Place the numbers from 1 to 9 in the squares below so that the difference between joined squares is odd. How many different ways can you do this?
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?
Can you see why 2 by 2 could be 5? Can you predict what 2 by 10 will be?
Ben and his mum are planting garlic. Use the interactivity to help you find out how many cloves of garlic they might have had.
Investigate the smallest number of moves it takes to turn these mats upside-down if you can only turn exactly three at a time.
Find out what a "fault-free" rectangle is and try to make some of your own.
If you have only four weights, where could you place them in order to balance this equaliser?
How have the numbers been placed in this Carroll diagram? Which labels would you put on each row and column?
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?
Have a go at this well-known challenge. Can you swap the frogs and toads in as few slides and jumps as possible?
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?
Use the information about Sally and her brother to find out how many children there are in the Brown family.
Choose four of the numbers from 1 to 9 to put in the squares so that the differences between joined squares are odd.
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?
Can you work out how to balance this equaliser? You can put more than one weight on a hook.
How many trains can you make which are the same length as Matt's, using rods that are identical?
In your bank, you have three types of coins. The number of spots shows how much they are worth. Can you choose coins to exchange with the groups given to make the same total?
What are the coordinates of the coloured dots that mark out the tangram? Try changing the position of the origin. What happens to the coordinates now?
Can you put the numbers from 1 to 15 on the circles so that no consecutive numbers lie anywhere along a continuous straight line?
What happens when you try and fit the triomino pieces into these two grids?
Use the interactivity to sort these numbers into sets. Can you give each set a name?
Can you fit the tangram pieces into the outline of Granma T?
Can you find all the different ways of lining up these Cuisenaire rods?
Try out the lottery that is played in a far-away land. What is the chance of winning?
Use the interactivities to complete these Venn diagrams.
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?
Make one big triangle so the numbers that touch on the small triangles add to 10.
Here are some rods that are different colours. How could I make a dark green rod using yellow and white rods?
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.
How many different rhythms can you make by putting two drums on the wheel?
If you hang two weights on one side of this balance, in how many different ways can you hang three weights on the other side for it to be balanced?
If there are 3 squares in the ring, can you place three different numbers in them so that their differences are odd? Try with different numbers of squares around the ring. What do you notice?
Choose 13 spots on the grid. Can you work out the scoring system? What is the maximum possible score?
How many triangles can you make using sticks that are 3cm, 4cm and 5cm long?
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?
How many right angles can you make using two sticks?
Ahmed has some wooden planks to use for three sides of a rabbit run against the shed. What quadrilaterals would he be able to make with the planks of different lengths?
Can you use the numbers on the dice to reach your end of the number line before your partner beats you?
Use the interactivity to help get a feel for this problem and to find out all the possible ways the balls could land.
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 cover the camel with these pieces?
Can you hang weights in the right place to make the equaliser balance?
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!
A simulation of target archery practice
Find out how we can describe the "symmetries" of this triangle and investigate some combinations of rotating and flipping it.
An animation that helps you understand the game of Nim.
An activity based on the game 'Pelmanism'. Set your own level of challenge and beat your own previous best score.
Use the interactivity to create some steady rhythms. How could you create a rhythm which sounds the same forwards as it does backwards?
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?