Just now I tweeted from https://twitter.com/jcrabtree with the goal of creating a complete set of pedagogies for the elementary arithmatrix that remain consistent from the Naturals to the Reals.
I have been researching the arithmatrix for many years. This research has spanned most of the great and famous mathematicians, from West and East, and has spanned 16 languages.
As yet, I do not believe any K-8 curriculum in the world has a consistent set of pedagogies that span the naturals, all the way to the reals. That has been the focus of my research since the 1980s as a mathematics historian/designer.
I would value your contribution highly. So please download the graphic and provide your suggestions for the color coding. By May 1st 2017 my goal is to make the entire arithmatrix both simple to teach and understand.