Richard Askey, University of Wisconsin

Geometry through the School Years
Richard Askey, University of Wisconsin-Madison
November 19, 2009

Abstract:  There has been a lot written about teaching arithmetic to children and the National Mathematics Advisory Panel had a focus on algebra and preparing students to take it.  Geometry has been ignored, yet it is the part of mathematics where our students do most poorly once one gets beyond the stage of names for different figures.  This talk with start with elementary school geometry.

One essential difference between a triangle and a quadrilateral is that a triangle is rigid while a quadrilateral is not.  This can easily be illustrated with fingers.  Other topics will include such things as how the same figures can be used to get the area of a triangle, the angle sum of a triangle and later even the addition formula for sines and cosines, and why there is a factor of 1/2 in the formula for the area of a triangle but 1/3 in the formula for the volume of a pyramid.