Factors and multiples

problem
Round and round the circle

Age

7 to 11

Challenge level

What happens if you join every second point on this circle? How about every third point? Try with different steps and see if you can predict what will happen.
problem
Sweets in a box

Age

7 to 11

Challenge level

How many different shaped boxes can you design for 36 sweets in one layer? Can you arrange the sweets so that no sweets of the same colour are next to each other in any direction?
problem
Bracelets

Age

7 to 11

Challenge level

Investigate the different shaped bracelets you could make from 18 different spherical beads. How do they compare if you use 24 beads?
problem
It figures

Age

7 to 11

Challenge level

Suppose we allow ourselves to use three numbers less than 10 and multiply them together. How many different products can you find? How do you know you've got them all?
problem
Pebbles

Age

7 to 11

Challenge level

Place four pebbles on the sand in the form of a square. Keep adding as few pebbles as necessary to double the area. How many extra pebbles are added each time?
list
Factors and multiples - secondary resources

Age

11 to 16

Challenge level

A collection of resources to support work on Factors and Multiples at Secondary level.
article
Can you find a perfect number?

Can you find any perfect numbers? Read this article to find out more...
article
Multiplication series: number arrays

This article for teachers describes how number arrays can be a useful representation for many number concepts.
article
Sums of squares and sums of cubes

An account of methods for finding whether or not a number can be written as the sum of two or more squares or as the sum of two or more cubes.
article
Telescoping functions

Take a complicated fraction with the product of five quartics top and bottom and reduce this to a whole number. This is a numerical example involving some clever algebra.