Filter by: Content type: ALL Problems Articles Games Stage: All Stage 1&2 Stage 2&3 Stage 3&4 Stage 4&5 Challenge level:
Imagine a wheel with different markings painted on it at regular intervals. Can you predict the colour of the 18th mark? The 100th mark?
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?
An environment which simulates working with Cuisenaire rods.
Investigate the smallest number of moves it takes to turn these mats upside-down if you can only turn exactly three at a time.
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 in them?
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?
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!
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?
Three beads are threaded on a circular wire and are coloured either red or blue. Can you find all four different combinations?
Can you see why 2 by 2 could be 5? Can you predict what 2 by 10 will be?
Try to stop your opponent from being able to split the piles of counters into unequal numbers. Can you find a strategy?
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?
A game for 2 people that can be played on line or with pens and paper. Combine your knowledege of coordinates with your skills of strategic thinking.
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?
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....?
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?
A card pairing game involving knowledge of simple ratio.
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?
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?
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?
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?
How many different triangles can you make on a circular pegboard that has nine pegs?
Find out how we can describe the "symmetries" of this triangle and investigate some combinations of rotating and flipping it.
Arrange the four number cards on the grid, according to the rules, to make a diagonal, vertical or horizontal line.
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?
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. . . .
Can you find all the different ways of lining up these Cuisenaire rods?
Use the interactivity to find all the different right-angled triangles you can make by just moving one corner of the starting triangle.
An interactive activity for one to experiment with a tricky tessellation
A game for 2 people that everybody knows. You can play with a friend or online. If you play correctly you never lose!
Can you complete this jigsaw of the multiplication square?
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?
NRICH December 2006 advent calendar - a new tangram for each day in the run-up to Christmas.
This 100 square jigsaw is written in code. It starts with 1 and ends with 100. Can you build it up?
Here is a chance to play a version of the classic Countdown Game.
Can you put the numbers 1 to 8 into the circles so that the four calculations are correct?
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?
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?
Have a go at this well-known challenge. Can you swap the frogs and toads in as few slides and jumps as possible?
Using angular.js to bind inputs to outputs
Our 2008 Advent Calendar has a 'Making Maths' activity for every day in the run-up to Christmas.
Choose a symbol to put into the number sentence.
A train building game for 2 players.
Can you put the numbers from 1 to 15 on the circles so that no consecutive numbers lie anywhere along a continuous straight line?
Choose 13 spots on the grid. Can you work out the scoring system? What is the maximum possible score?
In this activity, the computer chooses a times table and shifts it. Can you work out the table and the shift each time?
Use the sightings of the lion to guess the location of its lair.
How have the numbers been placed in this Carroll diagram? Which labels would you put on each row and column?