What this unit is about

Circles are around us everywhere. The circle is a shape we rely on heavily in our lives: wheels are circles, as are dinner plates, cups, lids on bottles, DVDs and cogs in machinery. We also use the image of a circle in expressions such as ‘the circle of life’ and ‘going around in circles’. We sit in circles, eat circular chapattis and preserve food in circular tins; we also ride bicycles and drive cars with wheels. So we are all exposed to circles – working and playing with them, or talking about them – from an early age.

Students come to school with an intuitive understanding of circles and their properties. This unit will explore how to use that intuitive knowledge effectively by asking ‘good’ questions that help students notice the important mathematical ideas of variance and invariance. This will help your students to develop a better theoretical understanding of the concepts.