Remember the graph paper you used at school, the kind that’s covered with tiny squares? It’s the perfect illustration of what mathematicians call a “periodic tiling of space”, with shapes covering an ...

Frank A. Farris does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond ...

Re "The New Math: Three Concepts in Two Years; Common Core drives new look at math instruction," July 22 article: In 2008, the National Mathematics Advisory Panel recommended that schools prepare more ...