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
Can you put the numbers 1 to 8 into the circles so that the four
calculations are correct?
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.
Arrange the four number cards on the grid, according to the rules,
to make a diagonal, vertical or horizontal line.
Can you put the numbers from 1 to 15 on the circles so that no
consecutive numbers lie anywhere along a continuous straight line?
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?
Here is a chance to play a version of the classic Countdown Game.
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....?
Our 2008 Advent Calendar has a 'Making Maths' activity for every
day in the run-up to Christmas.
Can you complete this jigsaw of the multiplication square?
An environment which simulates working with Cuisenaire rods.
This 100 square jigsaw is written in code. It starts with 1 and ends with 100. Can you build it up?
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?
Mr McGregor has a magic potting shed. Overnight, the number of
plants in it doubles. He'd like to put the same number of plants in
each of three gardens, planting one garden each day. Can he do it?
Try out the lottery that is played in a far-away land. What is the
chance of winning?
Use the interactivity to find all the different right-angled
triangles you can make by just moving one corner of the starting
Find out what a "fault-free" rectangle is and try to make some of
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?
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?
Can you see why 2 by 2 could be 5? Can you predict what 2 by 10
A game for 2 people that everybody knows. You can play with a
friend or online. If you play correctly you never lose!
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!
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?
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 find all the different ways of lining up these Cuisenaire
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?
How many different triangles can you make on a circular pegboard that has nine pegs?
Place the numbers 1 to 10 in the circles so that each number is the
difference between the two numbers just below it.
If you have only four weights, where could you place them in order
to balance this equaliser?
NRICH December 2006 advent calendar - a new tangram for each day in
the run-up to Christmas.
Cut four triangles from a square as shown in the picture. How many
different shapes can you make by fitting the four triangles back
This article gives you a few ideas for understanding the Got It! game and how you might find a winning strategy.
Imagine a wheel with different markings painted on it at regular
intervals. Can you predict the colour of the 18th mark? The 100th
Three beads are threaded on a circular wire and are coloured either red or blue. Can you find all four different combinations?
A train building game for 2 players.
Work out the fractions to match the cards with the same amount of
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?
The idea of this game is to add or subtract the two numbers on the dice and cover the result on the grid, trying to get a line of three. Are there some numbers that are good to aim for?
A game for 1 person to play on screen. Practise your number bonds
whilst improving your memory
Can you fit the tangram pieces into the outlines of these clocks?
Can you fit the tangram pieces into the outline of Little Ming playing the board game?
A card pairing game involving knowledge of simple ratio.
Exchange the positions of the two sets of counters in the least possible number of moves
Can you fit the tangram pieces into the outlines of the chairs?
Can you fit the tangram pieces into the outline of Granma T?
Practise your diamond mining skills and your x,y coordination in this homage to Pacman.
Can you find all the different triangles on these peg boards, and
find their angles?
Can you fit the tangram pieces into the outline of the telescope and microscope?