An article for teachers which discusses the differences between ratio and proportion, and invites readers to contribute their own thoughts.

The Man is much smaller than us. Can you use the picture of him next to a mug to estimate his height and how much tea he drinks?

Use the Cuisenaire rods environment to investigate ratio. Can you find pairs of rods in the ratio 3:2? How about 9:6?

The triangles in these sets are similar - can you work out the lengths of the sides which have question marks?

Use the ratio of cashew nuts to peanuts to find out how many peanuts Rachel has. What would the ratio be if Rachel and Marianne mixed their bags?

Read all about the number pi and the mathematicians who have tried to find out its value as accurately as possible.