Ben and his mum are planting garlic. Use the interactivity to help
you find out how many cloves of garlic they might have had.
Investigate the smallest number of moves it takes to turn these
mats upside-down if you can only turn exactly three at a time.
How many trains can you make which are the same length as Matt's, using rods that are identical?
Can you work out how to balance this equaliser? You can put more
than one weight on a hook.
How many different triangles can you draw on the dotty grid which each have one dot in the middle?
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?
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?
Here are some rods that are different colours. How could I make a dark green rod using yellow and white rods?
Can you find all the different ways of lining up these Cuisenaire
Use the interactivity to help get a feel for this problem and to find out all the possible ways the balls could land.
How many different rhythms can you make by putting two drums on the
Can you cover the camel with these pieces?
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?
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?
Arrange the four number cards on the grid, according to the rules,
to make a diagonal, vertical or horizontal line.
NRICH December 2006 advent calendar - a new tangram for each day in
the run-up to Christmas.
How many different ways can you find to join three equilateral
triangles together? Can you convince us that you have found them
What happens when you try and fit the triomino pieces into these
How many triangles can you make using sticks that are 3cm, 4cm and 5cm long?
Use the clues to colour each square.
Cut four triangles from a square as shown in the picture. How many
different shapes can you make by fitting the four triangles back
Our 2008 Advent Calendar has a 'Making Maths' activity for every
day in the run-up to Christmas.
Place the numbers 1 to 6 in the circles so that each number is the
difference between the two numbers just below it.
Find out what a "fault-free" rectangle is and try to make some of
A game for 2 people that everybody knows. You can play with a
friend or online. If you play correctly you never lose!
Using angular.js to bind inputs to outputs
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?
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?
An interactive activity for one to experiment with a tricky tessellation
Choose 13 spots on the grid. Can you work out the scoring system? What is the maximum possible score?
First Connect Three game for an adult and child. Use the dice numbers and either addition or subtraction to get three numbers in a straight line.
Exchange the positions of the two sets of counters in the least possible number of moves
Have a go at this well-known challenge. Can you swap the frogs and toads in as few slides and jumps as possible?
Train game for an adult and child. Who will be the first to make the train?
Can you find all the different triangles on these peg boards, and
find their angles?
Use the interactivity to investigate what kinds of triangles can be
drawn on peg boards with different numbers of pegs.
Stop the Clock game for an adult and child. How can you make sure you always win this game?
Find out how we can describe the "symmetries" of this triangle and
investigate some combinations of rotating and flipping it.
Choose four of the numbers from 1 to 9 to put in the squares so that the differences between joined squares are odd.
Incey Wincey Spider game for an adult and child. Will Incey get to the top of the drainpipe?
Move just three of the circles so that the triangle faces in the
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.
In your bank, you have three types of coins. The number of spots shows how much they are worth. Can you choose coins to exchange with the groups given to make the same total?
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!
Make one big triangle so the numbers that touch on the small triangles add to 10. You could use the interactivity to help you.
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?