The Math Projects Journal (MPJ) is "dedicated to improving mathematics education by empowering teachers with lessons and ideas" based on "four and a half" principles which are described on the website. This website offers a selection of free lesson plans and articles on pre-algebra, algebra, and geometry. A 300-page spiral bound book of lessons and articles published in the first five years of MPJ is also available for purchase, which then gives you access to periodic postings of new lessons online. Many of the lessons are from the MPJ's international readers and teachers are encouraged to submit their ideas. Readers can also post questions "about what to teach or how to teach it," which will then be answered by the editors or fellow readers. A Math Links section provides some additional mathematics education resources online.