Mr Gilderdale is playing a game with his class. What rule might he have chosen? How would you test your idea?

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

Use the interactivities to complete these Venn diagrams.

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?

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

Yasmin and Zach have some bears to share. Which numbers of bears can they share so that there are none left over?

Can you use the numbers on the dice to reach your end of the number line before your partner beats you?

How have the numbers been placed in this Carroll diagram? Which labels would you put on each row and column?

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

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?

Investigate the smallest number of moves it takes to turn these mats upside-down if you can only turn exactly three at a time.

Can you work out how to balance this equaliser? You can put more than one weight on a hook.

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

Choose four of the numbers from 1 to 9 to put in the squares so that the differences between joined squares are odd.

Can you complete this jigsaw of the multiplication square?

This article gives you a few ideas for understanding the Got It! game and how you might find a winning strategy.

Use the interactivity to sort these numbers into sets. Can you give each set a name?

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

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

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?

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.

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.

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

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 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.

Use the information about Sally and her brother to find out how many children there are in the Brown family.

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?

A game for 2 people that everybody knows. You can play with a friend or online. If you play correctly you never lose!

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?

An interactive activity for one to experiment with a tricky tessellation

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?

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?

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

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?

This game challenges you to locate hidden triangles in The White Box by firing rays and observing where the rays exit the Box.

The computer has made a rectangle and will tell you the number of spots it uses in total. Can you find out where the rectangle is?

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

These interactive dominoes can be dragged around the screen.

There are three versions of this challenge. The idea is to change the colour of all the spots on the grid. Can you do it in fewer throws of the dice?

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

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

How have the numbers been placed in this Carroll diagram? Which labels would you put on each row and column?

Incey Wincey Spider game for an adult and child. Will Incey get to the top of the drainpipe?