Arrange the four number cards on the grid, according to the rules,
to make a diagonal, vertical or horizontal line.
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....?
Investigate the smallest number of moves it takes to turn these
mats upside-down if you can only turn exactly three at a time.
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 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?
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 six toy ladybirds into the box so that there are two
ladybirds in every column and every row.
Place the numbers 1 to 6 in the circles so that each number is the
difference between the two numbers just below it.
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?
An odd version of tic tac toe
Can you work out how to balance this equaliser? You can put more
than one weight on a hook.
How have the numbers been placed in this Carroll diagram? Which
labels would you put on each row and column?
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?
Our 2008 Advent Calendar has a 'Making Maths' activity for every
day in the run-up to Christmas.
Here is a chance to play a version of the classic Countdown Game.
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?
An environment which simulates working with Cuisenaire rods.
Try to stop your opponent from being able to split the piles of counters into unequal numbers. Can you find a strategy?
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?
Choose four of the numbers from 1 to 9 to put in the squares so that the differences between joined squares are odd.
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?
Hover your mouse over the counters to see which ones will be
removed. Click to remover them. The winner is the last one to
remove a counter. How you can make sure you win?
Can you cover the camel with these pieces?
What happens when you try and fit the triomino pieces into these
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?
Use the interactivities to fill in these Carroll diagrams. How do you know where to place the numbers?
Can you put the numbers from 1 to 15 on the circles so that no
consecutive numbers lie anywhere along a continuous straight line?
Ben and his mum are planting garlic. Use the interactivity to help
you find out how many cloves of garlic they might have had.
Use the interactivity to find all the different right-angled
triangles you can make by just moving one corner of the starting
Try out the lottery that is played in a far-away land. What is the
chance of winning?
Use the clues to colour each square.
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 complete this jigsaw of the multiplication square?
Can you put the numbers 1 to 8 into the circles so that the four
calculations are correct?
Can you find all the different ways of lining up these Cuisenaire
Can you put the 25 coloured tiles into the 5 x 5 square so that no
column, no row and no diagonal line have tiles of the same colour
If you have only four weights, where could you place them in order
to balance this equaliser?
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?
Place the numbers 1 to 10 in the circles so that each number is the
difference between the two numbers just below it.
NRICH December 2006 advent calendar - a new tangram for each day in
the run-up to Christmas.
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?
Use your mouse to move the red and green parts of this disc. Can
you make images which show the turnings described?
You'll need two dice to play this game against a partner. Will Incey Wincey make it to the top of the drain pipe or the bottom of the drain pipe first?
How many triangles can you make using sticks that are 3cm, 4cm and 5cm long?
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?
Use the interactivity to find out how many quarter turns the man
must rotate through to look like each of the pictures.
This article gives you a few ideas for understanding the Got It! game and how you might find a winning strategy.
Make one big triangle so the numbers that touch on the small triangles add to 10. You could use the interactivity to help you.
How many different rhythms can you make by putting two drums on the