Use the interactivity to help get a feel for this problem and to find out all the possible ways the balls could land.

Place the numbers 1 to 6 in the circles so that each number is the difference between the two numbers just below it.

Here are some rods that are different colours. How could I make a yellow rod using white and red rods?

How many trains can you make which are the same length as Matt's and Katie's, using rods that are identical?

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?

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....?

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?

Have a go at this well-known challenge. Can you swap the frogs and toads in as few slides and jumps as possible?

Terry and Ali are playing a game with three balls. Is it fair that Terry wins when the middle ball is red?

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 in them?

Place six toy ladybirds into the box so that there are two ladybirds in every column and every row.

A game for 2 players that can be played online. Players take it in turns to select a word from the 9 words given. The aim is to select all the occurrences of the same letter.

Calculate the fractional amounts of money to match pairs of cards with the same value.

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?

A train building game for two players. Can you be the one to complete the train?

Can you find all the different triangles on these peg boards, and find their angles?

Place the numbers 1 to 10 in the circles so that each number is the difference between the two numbers just below it.

These interactive dominoes can be dragged around the screen.

The 2012 primary advent calendar features twenty-four of our posters, one for each day in the run-up to Christmas.

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

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.

Train game for an adult and child. Who will be the first to make the train?

Board Block game for two. Can you stop your partner from being able to make a shape on the board?

Stop the Clock game for an adult and child. How can you make sure you always win this game?

Take it in turns to make a triangle on the pegboard. Can you block your opponent?

A game for two people that can be played with pencils and paper. Combine your knowledge of coordinates with some strategic thinking.

Use the interactivities to fill in these Carroll diagrams. How do you know where to place the numbers?

Use the interactivity to find all the different right-angled triangles you can make by just moving one corner of the starting triangle.

Can you put the numbers 1 to 8 into the circles so that the four calculations are correct?

Add or subtract the two numbers on the spinners and try to complete a row of three. Are there some numbers that are good to aim for?

Practise your number bonds whilst improving your memory in this matching pairs game.

This is a game for two players. Can you find out how to be the first to get to 12 o'clock?

Watch this film carefully. Can you find a general rule for explaining when the dot will be this same distance from the horizontal axis?

Sort the houses in my street into different groups. Can you do it in any other ways?

How many different triangles can you draw on the dotty grid which each have one dot in the middle?

Play this well-known game against the computer where each player is equally likely to choose scissors, paper or rock. Why not try the variations too?

Use your mouse to move the red and green parts of this disc. Can you make images which show the turnings described?

Practise your tables skills and try to beat your previous best score in this interactive game.

How many different triangles can you make on a circular pegboard that has nine pegs?

Can you find a reliable strategy for choosing coordinates that will locate the treasure in the minimum number of guesses?

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

Arrange the four number cards on the grid, according to the rules, to make a diagonal, vertical or horizontal line.

Choose the size of your pegboard and the shapes you can make. Can you work out the strategies needed to block your opponent?

Seeing Squares game for an adult and child. Can you come up with a way of always winning this game?

Investigate which numbers make these lights come on. What is the smallest number you can find that lights up all the lights?