Can you find six numbers to go in the Daisy from which you can make all the numbers from 1 to a number bigger than 25?

Here is a chance to play a version of the classic Countdown 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?

Different combinations of the weights available allow you to make different totals. Which totals can you make?

Make your own double-sided magic square. But can you complete both sides once you've made the pieces?

This Sudoku requires you to do some working backwards before working forwards.

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

Use the differences to find the solution to this Sudoku.

A cinema has 100 seats. Show how it is possible to sell exactly 100 tickets and take exactly £100 if the prices are £10 for adults, 50p for pensioners and 10p for children.

This Sudoku, based on differences. Using the one clue number can you find the solution?

How many solutions can you find to this sum? Each of the different letters stands for a different number.

This article explains how to make your own magic square to mark a special occasion with the special date of your choice on the top line.

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

If you take a three by three square on a 1-10 addition square and multiply the diagonally opposite numbers together, what is the difference between these products. Why?

Find the values of the nine letters in the sum: FOOT + BALL = GAME

By selecting digits for an addition grid, what targets can you make?

Got It game for an adult and child. How can you play so that you know you will always win?

Five numbers added together in pairs produce: 0, 2, 4, 4, 6, 8, 9, 11, 13, 15 What are the five numbers?

Can you explain the strategy for winning this game with any target?

The letters in the following addition sum represent the digits 1 ... 9. If A=3 and D=2, what number is represented by "CAYLEY"?

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

Do you notice anything about the solutions when you add and/or subtract consecutive negative numbers?

How many ways can you find to put in operation signs (+ - x ÷) to make 100?

Crosses can be drawn on number grids of various sizes. What do you notice when you add opposite ends?

Charlie has made a Magic V. Can you use his example to make some more? And how about Magic Ls, Ns and Ws?

This article suggests some ways of making sense of calculations involving positive and negative numbers.

Some Games That May Be Nice or Nasty for an adult and child. Use your knowledge of place value to beat your opponent.

Investigate the different ways that fifteen schools could have given money in a charity fundraiser.

There are nasty versions of this dice game but we'll start with the nice ones...

Can you arrange these numbers into 7 subsets, each of three numbers, so that when the numbers in each are added together, they make seven consecutive numbers?

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

In the following sum the letters A, B, C, D, E and F stand for six distinct digits. Find all the ways of replacing the letters with digits so that the arithmetic is correct.

There are exactly 3 ways to add 4 odd numbers to get 10. Find all the ways of adding 8 odd numbers to get 20. To be sure of getting all the solutions you will need to be systematic. What about. . . .

Find out about Magic Squares in this article written for students. Why are they magic?!

Ann thought of 5 numbers and told Bob all the sums that could be made by adding the numbers in pairs. The list of sums is 6, 7, 8, 8, 9, 9, 10,10, 11, 12. Help Bob to find out which numbers Ann was. . . .

Delight your friends with this cunning trick! Can you explain how it works?

The country Sixtania prints postage stamps with only three values 6 lucres, 10 lucres and 15 lucres (where the currency is in lucres).Which values cannot be made up with combinations of these postage. . . .

Try out some calculations. Are you surprised by the results?

What is the sum of all the digits in all the integers from one to one million?

A combination mechanism for a safe comprises thirty-two tumblers numbered from one to thirty-two in such a way that the numbers in each wheel total 132... Could you open the safe?

This challenge extends the Plants investigation so now four or more children are involved.

Fancy a game of cricket? Here is a mathematical version you can play indoors without breaking any windows.

Using the 8 dominoes make a square where each of the columns and rows adds up to 8

15 = 7 + 8 and 10 = 1 + 2 + 3 + 4. Can you say which numbers can be expressed as the sum of two or more consecutive integers?

What happens when you add a three digit number to its reverse?

When I type a sequence of letters my calculator gives the product of all the numbers in the corresponding memories. What numbers should I store so that when I type 'ONE' it returns 1, and when I type. . . .