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.
Here is a chance to play a version of the classic Countdown Game.
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?
This article gives you a few ideas for understanding the Got It! game and how you might find a winning strategy.
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?
Our 2008 Advent Calendar has a 'Making Maths' activity for every day in the run-up to Christmas.
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....?
Can you work out how to balance this equaliser? You can put more than one weight on a hook.
How many trains can you make which are the same length as Matt's, using rods that are identical?
Try to stop your opponent from being able to split the piles of counters into unequal numbers. Can you find a strategy?
Find out what a "fault-free" rectangle is and try to make some of your own.
Arrange the four number cards on the grid, according to the rules, to make a diagonal, vertical or horizontal line.
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?
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?
NRICH December 2006 advent calendar - a new tangram for each day in the run-up to Christmas.
An odd version of tic tac toe
Incey Wincey Spider game for an adult and child. Will Incey get to the top of the drainpipe?
If there are 3 squares in the ring, can you place three different numbers in them so that their differences are odd? Try with different numbers of squares around the ring. What do you notice?
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?
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?
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?
Place six toy ladybirds into the box so that there are two ladybirds in every column and every row.
Twenty four games for 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 activity for one to experiment with a tricky tessellation
A train building game for 2 players.
If you have only four weights, where could you place them in order to balance this equaliser?
Exchange the positions of the two sets of counters in the least possible number of moves
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?
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?
Place the numbers 1 to 6 in the circles so that each number is the difference between the two numbers just below it.
How many different triangles can you make on a circular pegboard that has nine pegs?
Can you find all the different triangles on these peg boards, and find their angles?
Use the clues to colour each square.
Choose four of the numbers from 1 to 9 to put in the squares so that the differences between joined squares are odd.
A generic circular pegboard resource.
Use the interactivity to investigate what kinds of triangles can be drawn on peg boards with different numbers of pegs.
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?
How have the numbers been placed in this Carroll diagram? Which labels would you put on each row and column?
Move just three of the circles so that the triangle faces in the opposite direction.
Stop the Clock game for an adult and child. How can you make sure you always win this game?
Place the numbers 1 to 10 in the circles so that each number is the difference between the two numbers just below it.
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!
A variant on the game Alquerque
Can you fit the tangram pieces into the outlines of these people?
Can you fit the tangram pieces into the outline of this brazier for roasting chestnuts?
Can you fit the tangram pieces into the outlines of these clocks?
Can you fit the tangram pieces into the outline of the child walking home from school?
Can you fit the tangram pieces into the outlines of the lobster, yacht and cyclist?