Cut four triangles from a square as shown in the picture. How many
different shapes can you make by fitting the four triangles back
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?
How many different rhythms can you make by putting two drums on the
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
Use the clues to colour each square.
What happens when you try and fit the triomino pieces into these
Can you cover the camel with these pieces?
Use the interactivity to help get a feel for this problem and to find out all the possible ways the balls could land.
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 work out how to balance this equaliser? You can put more
than one weight on a hook.
Here are some rods that are different colours. How could I make a dark green rod using yellow and white rods?
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?
Ben and his mum are planting garlic. Use the interactivity to help
you find out how many cloves of garlic they might have had.
How many triangles can you make using sticks that are 3cm, 4cm and 5cm long?
Use your mouse to move the red and green parts of this disc. Can
you make images which show the turnings described?
How many different ways can you find to join three equilateral
triangles together? Can you convince us that you have found them
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....?
How many different triangles can you draw on the dotty grid which each have one dot in the middle?
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?
Use the interactivity to find all the different right-angled
triangles you can make by just moving one corner of the starting
Investigate the smallest number of moves it takes to turn these
mats upside-down if you can only turn exactly three at a time.
Place the numbers 1 to 6 in the circles so that each number is the
difference between the two numbers just below it.
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
How many trains can you make which are the same length as Matt's, using rods that are identical?
Sort the houses in my street into different groups. Can you do it in any other ways?
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?
Explore the different tunes you can make with these five gourds.
What are the similarities and differences between the two tunes you
Find out how we can describe the "symmetries" of this triangle and
investigate some combinations of rotating and flipping it.
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.
Our 2008 Advent Calendar has a 'Making Maths' activity for every
day in the run-up to Christmas.
Place six toy ladybirds into the box so that there are two
ladybirds in every column and every row.
Can you put the numbers 1 to 8 into the circles so that the four
calculations are correct?
Can you put the numbers from 1 to 15 on the circles so that no
consecutive numbers lie anywhere along a continuous straight line?
NRICH December 2006 advent calendar - a new tangram for each day in
the run-up to Christmas.
Investigate the different sounds you can make by putting the owls
and donkeys on the wheel.
Board Block game for two. Can you stop your partner from being able to make a shape on the board?
An interactive activity for one to experiment with a tricky tessellation
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. . . .
Train game for an adult and child. Who will be the first to make the train?
Watch this film carefully. Can you find a general rule for
explaining when the dot will be this same distance from the
Terry and Ali are playing a game with three balls. Is it fair that
Terry wins when the middle ball is red?
Complete the squares - but be warned some are trickier than they
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.
A game to be played against the computer, or in groups. Pick a 7-digit number. A random digit is generated. What must you subract to remove the digit from your number? the first to zero wins.
A game for 2 people that everybody knows. You can play with a
friend or online. If you play correctly you never lose!
Find out what a "fault-free" rectangle is and try to make some of
Using angular.js to bind inputs to outputs