The circle Class activity Play

The circle Whiteboard presentation Play

The circle and its equation Animation Play

The circle and the equilateral triangle Whiteboard exercise Play

The circle and the equilateral triangle Student activity Play

The circle and the oval Animation Play

The circle as a locus Animation Play

The circle inscribed in a square Whiteboard exercise Play

The circle with centre at an arbitrary point Whiteboard exercise Play

The circle with centre at the origin Whiteboard exercise Play

The circle with centre at the origin Student activity Play

The circle's circumference Whiteboard exercise Play

The circle's circumference and its diameter Student activity Play

The circle's diameter Whiteboard exercise Play

The circumcentre of a triangle Student activity Play

The circumference and the astonishing number Pi Whiteboard exercise Play

The circumference and the astonishing number Pi Student activity Play

The circumference of the box Animation Play

The cosine and coordinates of the points Animation Play

The cosine of an arbitrary angle Student activity Play

The data collected by Lena Animation Play

The distance between the centres of circles Student activity Play

The equation of a circle going through a point Student activity Play

The equation of a circle through a point Whiteboard exercise Play

The equation of a circle with centre at an arbitrary point Simulation Play