Can you work out how to balance this equaliser? You can put more
than one weight on a hook.
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?
How many trains can you make which are the same length as Matt's,
using rods that are identical?
Can you find all the different ways of lining up these Cuisenaire
Use the clues to colour each square.
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?
Here are some rods that are different colours. How could I make a dark green rod using yellow and white rods?
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....?
Ben and his mum are planting garlic. Use the interactivity to help
you find out how many cloves of garlic they might have had.
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?
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 cover the camel with these pieces?
What happens when you try and fit the triomino pieces into these
How many different rhythms can you make by putting two drums on the
Use the interactivity to help get a feel for this problem and to find out all the possible ways the balls could land.
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?
Cut four triangles from a square as shown in the picture. How many
different shapes can you make by fitting the four triangles back
Arrange the four number cards on the grid, according to the rules,
to make a diagonal, vertical or horizontal line.
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?
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 from 1 to 15 on the circles so that no
consecutive numbers lie anywhere along a continuous straight line?
Play this well-known game against the computer where each player is
equally likely to choose scissors, paper or rock. Why not try the
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?
How many triangles can you make using sticks that are 3cm, 4cm and 5cm long?
A generic circular pegboard resource.
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 different triangles can you make on a circular pegboard
that has nine pegs?
NRICH December 2006 advent calendar - a new tangram for each day in
the run-up to Christmas.
Match the halves.
Place six toy ladybirds into the box so that there are two
ladybirds in every column and every row.
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!
Three beads are threaded on a circular wire and are coloured either red or blue. Can you find all four different combinations?
Investigate the different sounds you can make by putting the owls
and donkeys on the wheel.
An odd version of tic tac toe
Use the interactivity to find out how many quarter turns the man
must rotate through to look like each of the pictures.
Exchange the positions of the two sets of counters in the least possible number of moves
Try to stop your opponent from being able to split the piles of counters into unequal numbers. Can you find a strategy?
How many different ways can you find to join three equilateral
triangles together? Can you convince us that you have found them
Use your mouse to move the red and green parts of this disc. Can
you make images which show the turnings described?
Find out how we can describe the "symmetries" of this triangle and
investigate some combinations of rotating and flipping it.
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 interactivity to find all the different right-angled
triangles you can make by just moving one corner of the starting
Twenty four games for the run-up to Christmas.
Try out the lottery that is played in a far-away land. What is the
chance of winning?
Complete the squares - but be warned some are trickier than they
A variant on the game Alquerque
Can you put the numbers 1 to 8 into the circles so that the four
calculations are correct?
Have a go at this well-known challenge. Can you swap the frogs and toads in as few slides and jumps as possible?
Sort the houses in my street into different groups. Can you do it in any other ways?
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?