Counting will get you nowhere. Try a little combinatorics instead. By Kenneth Chang A couple of weeks ago, I wrote about a viral math problem — 8÷2(2+2) = ? — that drew the disdain of many ...

Big Idea – We can describe, measure, and compare spatial relationships. to build on students' knowledge of triangle and develop students' reasoning with properties of different classes of triangles to ...

In our mind’s eye, the universe seems to go on forever. But using geometry we can explore a variety of three-dimensional shapes that offer alternatives to “ordinary” infinite space. When you gaze out ...