The concept of coordinates and graphs is almost always introduced using square Cartesian grids with the coordinates representing distances from an origin. There is no reason why an introduction to coordinates and graphs shouldn’t use distance and angles with a grid comprising circles and lines, i.e. a polar grid.

PRIMARY: position of a point in terms of distance and angle, tabulating values, drawing polar graphs.

SECONDARY: plus instruction to some well-known curves, eg cardiod, Limaçon, investigation of n-leaf roses.

SIXTH FORM: plus areas in polar coordinates, equi-angular spiral.

Copyright Maths Discovery 2015