The Arithmetic Teacher index for volume 3.
This article is available to members of NCTM who subscribe to
Teaching Children Mathematics. Don't miss outjoin now or upgrade your membership. You may also purchase this article now for online access.
Putting a twist on a popular mathematical tool, this collection
of activities shows how putting a number 1 in the bottom-left cell and a 100 in
the top-right cell can better support student reasoning.