What happens when you add the digits of a number then multiply the result by 2 and you keep doing this? You could try for different numbers and different rules.

"Ip dip sky blue! Who's 'it'? It's you!" Where would you position yourself so that you are 'it' if there are two players? Three players ...?

Can you find all the ways to get 15 at the top of this triangle of numbers?

This group activity will encourage you to share calculation strategies and to think about which strategy might be the most efficient.

Tom and Ben visited Numberland. Use the maps to work out the number of points each of their routes scores.

Ten cards are put into five envelopes so that there are two cards in each envelope. The sum of the numbers inside it is written on each envelope. What numbers could be inside the envelopes?

Lolla bought a balloon at the circus. She gave the clown six coins to pay for it. What could Lolla have paid for the balloon?

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

What could the half time scores have been in these Olympic hockey matches?

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

Can you use the information to find out which cards I have used?

Can you put the numbers 1-5 in the V shape so that both 'arms' have the same total?

Sweets are given out to party-goers in a particular way. Investigate the total number of sweets received by people sitting in different positions.

Tim had nine cards each with a different number from 1 to 9 on it. How could he have put them into three piles so that the total in each pile was 15?

There is a clock-face where the numbers have become all mixed up. Can you find out where all the numbers have got to from these ten statements?

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?

Look at what happens when you take a number, square it and subtract your answer. What kind of number do you get? Can you prove it?

Ram divided 15 pennies among four small bags. He could then pay any sum of money from 1p to 15p without opening any bag. How many pennies did Ram put in each bag?

How could you arrange at least two dice in a stack so that the total of the visible spots is 18?

The value of the circle changes in each of the following problems. Can you discover its value in each problem?

What happens when you add three numbers together? Will your answer be odd or even? How do you know?

Amy has a box containing domino pieces but she does not think it is a complete set. She has 24 dominoes in her box and there are 125 spots on them altogether. Which of her domino pieces are missing?

Use your addition and subtraction skills, combined with some strategic thinking, to beat your partner at this game.

This big box multiplies anything that goes inside it by the same number. If you know the numbers that come out, what multiplication might be going on in the box?

This problem is designed to help children to learn, and to use, the two and three times tables.

There are six numbers written in five different scripts. Can you sort out which is which?

Roll two red dice and a green dice. Add the two numbers on the red dice and take away the number on the green. What are all the different possibilities that could come up?

An investigation involving adding and subtracting sets of consecutive numbers. Lots to find out, lots to explore.

Exploring the structure of a number square: how quickly can you put the number tiles in the right place on the grid?

Four of these clues are needed to find the chosen number on this grid and four are true but do nothing to help in finding the number. Can you sort out the clues and find the number?

An activity centred around observations of dots and how we visualise number arrangement patterns.

Look at three 'next door neighbours' amongst the counting numbers. Add them together. What do you notice?

In this game for two players, the idea is to take it in turns to choose 1, 3, 5 or 7. The winner is the first to make the total 37.

Can you predict when you'll be clapping and when you'll be clicking if you start this rhythm? How about when a friend begins a new rhythm at the same time?

Four bags contain a large number of 1s, 3s, 5s and 7s. Pick any ten numbers from the bags above so that their total is 37.

You are organising a school trip and you need to write a letter to parents to let them know about the day. Use the cards to gather all the information you need.

Use these four dominoes to make a square that has the same number of dots on each side.

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.

A task which depends on members of the group noticing the needs of others and responding.

Use the 'double-3 down' dominoes to make a square so that each side has eight dots.

A task which depends on members of the group noticing the needs of others and responding.

Can you find different ways of showing the same fraction? Try this matching game and see.