I read the article. Like the idea a lot. I think this could work in the middle school. It sounds like he put the resources online using a Creative Commons license so that others can copy them.
Agreed, tried lots of mind mapping tools, this one seems to rank towards the top on ease of use. The fact that it can be integrated with Google apps makes it all the more attractive to us at AISB.
The Geoboard is a tool for exploring a variety of mathematical topics introduced in the elementary and middle grades. Learners stretch bands around pegs to form line segments and polygons and make discoveries about perimeter, area, angles, congruence, fractions, and more.