Investigate the smallest number of moves it takes to turn these mats upside-down if you can only turn exactly three at a time.
How many trains can you make which are the same length as Matt's, using rods that are identical?
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?
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 hang weights in the right place to make the equaliser balance?
Ben and his mum are planting garlic. Use the interactivity to help you find out how many cloves of garlic they might have had.
Can you complete this jigsaw of the multiplication square?
Can you complete this jigsaw of the 100 square?
Can you put the numbers from 1 to 15 on the circles so that no consecutive numbers lie anywhere along a continuous straight line?
Place the numbers 1 to 6 in the circles so that each number is the difference between the two numbers just below it.
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?
Can you work out how to balance this equaliser? You can put more than one weight on a hook.
Use the information about Sally and her brother to find out how many children there are in the Brown family.
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?
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?
How many different triangles can you make on a circular pegboard that has nine pegs?
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?
Make one big triangle so the numbers that touch on the small triangles add to 10.
Move just three of the circles so that the triangle faces in the opposite direction.
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?
Use the interactivity to find all the different right-angled triangles you can make by just moving one corner of the starting triangle.
How many different ways can you find to join three equilateral triangles together? Can you convince us that you have found them all?
How many triangles can you make using sticks that are 3cm, 4cm and 5cm long?
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?
How many right angles can you make using two sticks?
If you have only four weights, where could you place them in order to balance this equaliser?
Choose a symbol to put into the number sentence.
This 100 square jigsaw is written in code. It starts with 1 and ends with 100. Can you build it up?
Can you make a cycle of pairs that add to make a square number using all the numbers in the box below, once and once only?
Use the clues to colour each square.
These interactive dominoes can be dragged around the screen.
Place the numbers 1 to 10 in the circles so that each number is the difference between the two numbers just below it.
Use the interactivities to complete these Venn diagrams.
Can you use the numbers on the dice to reach your end of the number line before your partner beats you?
Start by putting one million (1 000 000) into the display of your calculator. Can you reduce this to 7 using just the 7 key and add, subtract, multiply, divide and equals as many times as you like?
Can you find all the different ways of lining up these Cuisenaire rods?
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?
Complete the squares - but be warned some are trickier than they look!
Use the interactivity to help get a feel for this problem and to find out all the possible ways the balls could land.
Can you see why 2 by 2 could be 5? Can you predict what 2 by 10 will be?
Can you cover the camel with these pieces?
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....?
Here are some rods that are different colours. How could I make a dark green rod using yellow and white rods?
Use the interactivities to fill in these Carroll diagrams. How do you know where to place the numbers?
What happens when you try and fit the triomino pieces into these two grids?
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?
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?
Place six toy ladybirds into the box so that there are two ladybirds in every column and every row.
Use the number weights to find different ways of balancing the equaliser.