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

Find the frequency distribution for ordinary English, and use it to help you crack the code.

Mr McGregor has a magic potting shed. Overnight, the number of plants in it doubles. He'd like to put the same number of plants in each of three gardens, planting one garden each day. Can he do it?

This 100 square jigsaw is written in code. It starts with 1 and ends with 100. Can you build it up?

Can you beat the computer in the challenging strategy game?

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?

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.

Try entering different sets of numbers in the number pyramids. How does the total at the top change?

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

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

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....?

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

Can you complete this jigsaw of the multiplication square?

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

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 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.

Here is a chance to play a version of the classic Countdown Game.

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?

Here is a chance to play a fractions version of the classic Countdown Game.

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

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

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?

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 explain the strategy for winning this game with any target?

The number of plants in Mr McGregor's magic potting shed increases overnight. He'd like to put the same number of plants in each of his gardens, planting one garden each day. How can he do it?

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

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

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

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?

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

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

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

The aim of the game is to slide the green square from the top right hand corner to the bottom left hand corner in the least number of moves.

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

A game for two people, or play online. Given a target number, say 23, and a range of numbers to choose from, say 1-4, players take it in turns to add to the running total to hit their target.

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

A game in which players take it in turns to choose a number. Can you block your opponent?

Do you know how to find the area of a triangle? You can count the squares. What happens if we turn the triangle on end? Press the button and see. Try counting the number of units in the triangle now. . . .

What shaped overlaps can you make with two circles which are the same size?

Each light in this interactivity turns on according to a rule. What happens when you enter different numbers? Can you find the smallest number that lights up all four lights?

We can show that (x + 1)² = x² + 2x + 1 by considering the area of an (x + 1) by (x + 1) square. Show in a similar way that (x + 2)² = x² + 4x + 4

When number pyramids have a sequence on the bottom layer, some interesting patterns emerge...

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.

Can you find the pairs that represent the same amount of money?

Can you find a relationship between the number of dots on the circle and the number of steps that will ensure that all points are hit?

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?