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!
Choose a symbol to put into the number sentence.
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?
Can you see why 2 by 2 could be 5? Can you predict what 2 by 10
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?
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?
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.
Investigate the smallest number of moves it takes to turn these
mats upside-down if you can only turn exactly three at a time.
Imagine a wheel with different markings painted on it at regular
intervals. Can you predict the colour of the 18th mark? The 100th
Try to stop your opponent from being able to split the piles of counters into unequal numbers. Can you find a strategy?
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?
A generic circular pegboard resource.
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?
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?
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?
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
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 activity for one to experiment with a tricky tessellation
NRICH December 2006 advent calendar - a new tangram for each day in
the run-up to Christmas.
A game for 2 people that everybody knows. You can play with a
friend or online. If you play correctly you never lose!
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. . . .
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?
Can you make the green spot travel through the tube by moving the
yellow spot? Could you draw a tube that both spots would follow?
Can you put the numbers 1 to 8 into the circles so that the four
calculations are correct?
Here is a chance to play a version of the classic Countdown Game.
A card pairing game involving knowledge of simple ratio.
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?
Using angular.js to bind inputs to outputs
Choose 13 spots on the grid. Can you work out the scoring system? What is the maximum possible score?
Place the numbers 1 to 10 in the circles so that each number is the
difference between the two numbers just below it.
Our 2008 Advent Calendar has a 'Making Maths' activity for every
day in the run-up to Christmas.
How have the numbers been placed in this Carroll diagram? Which
labels would you put on each row and column?
A train building game for 2 players.
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?
This article gives you a few ideas for understanding the Got It! game and how you might find a winning strategy.
Use the Cuisenaire rods environment to investigate ratio. Can you
find pairs of rods in the ratio 3:2? How about 9:6?
Investigate how the four L-shapes fit together to make an enlarged
L-shape. You could explore this idea with other shapes too.
Use the interactivity to find all the different right-angled
triangles you can make by just moving one corner of the starting
How many different triangles can you make on a circular pegboard
that has nine pegs?
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!
Find out how we can describe the "symmetries" of this triangle and
investigate some combinations of rotating and flipping it.
Choose the size of your pegboard and the shapes you can make. Can
you work out the strategies needed to block your opponent?
Three beads are threaded on a circular wire and are coloured either red or blue. Can you find all four different combinations?
Can you find all the different ways of lining up these Cuisenaire
Use the interactivity to create some steady rhythms. How could you
create a rhythm which sounds the same forwards as it does
This 100 square jigsaw is written in code. It starts with 1 and
ends with 100. Can you build it up?
Try out the lottery that is played in a far-away land. What is the
chance of winning?