Archive for November 2010
What does it mean to know a number? Pi for elementary teachers
Posted by: Gary Ernest Davis on: November 12, 2010
Area and “amount of stuff” The area of a region is often colloquially thought of as the “amount of stuff” in that region. This is not a good way of thinking about area because it leads to odd thinking such as the area of a region does not change if the perimeter changes “because the […]
Adding structure to solve a problem
Posted by: Gary Ernest Davis on: November 9, 2010
James Tanton (@jamestanton) tweeted the following problem: “25 people stand in a 5×5 grid of squares,1 per cell. At blow of whistle each is to take one step L, R ,U or D to a new cell, 1 per cell. How?” The problem does not state the grid is in a plane, but if, for […]
