Our 2008 Advent Calendar has a 'Making Maths' activity for every day in the run-up to Christmas.

Choose 13 spots on the grid. Can you work out the scoring system? What is the maximum possible score?

Use the interactivity to find out how many quarter turns the man must rotate through to look like each of the pictures.

Can you sort these triangles into three different families and explain how you did it?

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?

What does the overlap of these two shapes look like? Try picturing it in your head and then use the interactivity to test your prediction.

Complete the squares - but be warned some are trickier than they look!

Can you hang weights in the right place to make the equaliser balance?

NRICH December 2006 advent calendar - a new tangram for each day in the run-up to Christmas.

Move just three of the circles so that the triangle faces in the opposite direction.

Use the interactivity to create some steady rhythms. How could you create a rhythm which sounds the same forwards as it does backwards?

Twenty four games for the run-up to Christmas.

Can you complete this jigsaw of the multiplication square?

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?

If you can post the triangle with either the blue or yellow colour face up, how many ways can it be posted altogether?

How many right angles can you make using two sticks?

Use the number weights to find different ways of balancing the equaliser.

Imagine a wheel with different markings painted on it at regular intervals. Can you predict the colour of the 18th mark? The 100th mark?

Arrange any number of counters from these 18 on the grid to make a rectangle. What numbers of counters make rectangles? How many different rectangles can you make with each number of counters?

In this activity, the computer chooses a times table and shifts it. Can you work out the table and the shift each time?

Can you fit the tangram pieces into the outlines of the lobster, yacht and cyclist?

Can you work out what is wrong with the cogs on a UK 2 pound coin?

An interactive game to be played on your own or with friends. Imagine you are having a party. Each person takes it in turns to stand behind the chair where they will get the most chocolate.

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.

Use the interactivity to make this Islamic star and cross design. Can you produce a tessellation of regular octagons with two different types of triangle?

Three beads are threaded on a circular wire and are coloured either red or blue. Can you find all four different combinations?

If you have only four weights, where could you place them in order to balance this equaliser?

Use the Cuisenaire rods environment to investigate ratio. Can you find pairs of rods in the ratio 3:2? How about 9:6?

Can you logically construct these silhouettes using the tangram pieces?

Find out how we can describe the "symmetries" of this triangle and investigate some combinations of rotating and flipping it.

What shaped overlaps can you make with two circles which are the same size? What shapes are 'left over'? What shapes can you make when the circles are different sizes?

This activity challenges you to make collections of shapes. Can you give your collection a name?

Try to stop your opponent from being able to split the piles of counters into unequal numbers. Can you find a strategy?

What is the greatest number of squares you can make by overlapping three squares?

Use the interactivity or play this dice game yourself. How could you make it fair?

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?

Can you fit the tangram pieces into the outline of the child walking home from school?

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. . . .

Can you fit the tangram pieces into the outlines of the chairs?

Work out the fractions to match the cards with the same amount of money.

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?

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?