Euler found four whole numbers such that the sum of any two of the numbers is a perfect square...

The diagram illustrates the formula: 1 + 3 + 5 + ... + (2n - 1) = n² Use the diagram to show that any odd number is the difference of two squares.

If a sum invested gains 10% each year how long before it has doubled its value?

However did we manage before calculators? Is there an efficient way to do a square root if you have to do the work yourself?

Use an interactive Excel spreadsheet to explore number in this exciting game!

A simple file for the Interactive whiteboard or PC screen, demonstrating equivalent fractions.

Use an Excel spreadsheet to explore long multiplication.

Use Excel to practise adding and subtracting fractions.

A group of interactive resources to support work on percentages Key Stage 4.

What day of the week were you born on? Do you know? Here's a way to find out.

Use an Excel to investigate division. Explore the relationships between the process elements using an interactive spreadsheet.

An Excel spreadsheet with an investigation.

Use Excel to investigate the effect of translations around a number grid.

Use an interactive Excel spreadsheet to investigate factors and multiples.

Using an understanding that 1:2 and 2:3 were good ratios, start with a length and keep reducing it to 2/3 of itself. Each time that took the length under 1/2 they doubled it to get back within range.

Use Excel to explore multiplication of fractions.

In how many ways can a pound (value 100 pence) be changed into some combination of 1, 2, 5, 10, 20 and 50 pence coins?

What does this number mean ? Which order of 1, 2, 3 and 4 makes the highest value ? Which makes the lowest ?

A ribbon is nailed down with a small amount of slack. What is the largest cube that can pass under the ribbon ?

Take ten sticks in heaps any way you like. Make a new heap using one from each of the heaps. By repeating that process could the arrangement 7 - 1 - 1 - 1 ever turn up, except by starting with it?

A fire-fighter needs to fill a bucket of water from the river and take it to a fire. What is the best point on the river bank for the fire-fighter to fill the bucket ?.

An aluminium can contains 330 ml of cola. If the can's diameter is 6 cm what is the can's height?

It's like 'Peaches Today, Peaches Tomorrow' but interestingly generalized.

What is the greatest volume you can get for a rectangular (cuboid) parcel if the maximum combined length and girth are 2 metres?

Start with two numbers and generate a sequence where the next number is the mean of the last two numbers...

Substitute -1, -2 or -3, into an algebraic expression and you'll get three results. Is it possible to tell in advance which of those three will be the largest ?

A number of useful techniques that can extend your use of Excel.

How much peel does an apple have?

This investigation uses Excel to optimise a characteristic of interest.

Learn how to use composite bar charts in Excel.

A heap of beads was shared out by a professional bead sharer. Use the information given to find out how many beads there were at the start.

If you take two integers and look at the difference between the square of each value, there is a nice relationship between the original numbers and that difference. Can you find the pattern using. . . .

Take any pair of numbers, say 9 and 14. Take the larger number, fourteen, and count up in 14s. Then divide each of those values by the 9, and look at the remainders.

I have an unlimited supply of planks, of lengths 7 and 9 units. Putting planks end to end, what total lengths can be achieved? Use Excel to investigate.

The heptathlon is an athletics competition consisting of 7 events. Can you make sense of the scoring system in order to advise a heptathlete on the best way to reach her target?

With access to weather station data, what interesting questions can you investigate?

A plastic funnel is used to pour liquids through narrow apertures. What shape funnel would use the least amount of plastic to manufacture for any specific volume ?

Your school has been left a million pounds in the will of an ex- pupil. What model of investment and spending would you use in order to ensure the best return on the money?

Learn how to use increment buttons and scroll bars to create interactive Excel resources.

When is 7^n + 3^n a multiple of 10? Use Excel to investigate, and try to explain what you find out.

Learn how to make a simple table using Excel.

Investigate factors and multiples using this interactive Excel spreadsheet. Use the increment buttons for experimentation and feedback.

Use an Excel spreadsheet to approximate a decimal using trial and improvement.

Learn how to use lookup functions to create exciting interactive Excel spreadsheets.

Use Excel to investigate digit sums of multiples of three. Can you explain your findings?

Use Excel to investigate remainders and divisors. Was your result predictable?

Learn how to use logic tests to create interactive resources using Excel.

Learn how to use the Excel functions LCM and GCD.

Choose four numbers and make two fractions. Use an Excel spreadsheet to investigate their properties. Can you generalise?