A triangle and circles Student activity Play

An enlargement Simulation Play

An isosceles trapezoid and a circle Whiteboard exercise Play

An isosceles trapezoid and a circle Student activity Play

Angle bisector Student activity Play

Angle bisector Animation Play

Angles in a circle Whiteboard exercise Play

Angles in a circle Student activity Play

Angles on a straight line and angles round a point Student activity Play

Another form of the equation of the circle Animation Play

Another form of the equation of the circle Student activity Play

Arcs Whiteboard exercise Play

Arcs Student activity Play

Area under enlargement – a heptagon Whiteboard exercise Play

Areas of images of figures under enlargement Student activity Play

Areas under enlargement Animation Play

Arithmetic mean – 'balancing point' of the data Whiteboard exercise Play

Arithmetic mean – 'balancing point' of the data Student activity Play

Average monthly temperatures Whiteboard exercise Play

Balancing point Animation Play

Central and inscribed angles on the same arc Student activity Play

Central symmetry Animation Play

Centre of a circle at an arbitrary point Animation Play

Centre of enlargement Whiteboard exercise Play

Centre of enlargement Student activity Play