The goal of Math Bits is to offer "fun, yet challenging, lessons and activities." The site was created by two mathematics educators intent on increasing the love of math. The resources provided here are divided into more than two dozen categories, including algebra and geometry. Visitors should also note the Math and the Movies area, as it contains some great ideas on ways to teach math using...

PBS TeacherLine provides teachers with "online professional development in mathematics and technology integration." The site offers online courses, facilitated discussions, self-paced professional development, as well as online resources and tools that can be used to plan your professional development. PBS member stations offer the courses for a fee but resources on Mathematics, Science,...

The Freudenthal Institute is part of Utrecht University in the Netherlands and conducts research on math education. The goals are "to understand and improve the teaching of arithmetic and mathematics at all levels, but particularly in kindergarten, primary, secondary and vocational education." The Freudenthal Institute has developed a theoretical approach known as Realistic Mathematics Education,...

The Mathematical Association of America has developed the Innovative Teaching Exchange in order to facilitate the exchange of interesting and compelling teaching resources from a wide range of educators. As their site indicates, "The intention is to encourage more experimentation with more methods than the traditional lecture/questions method." Currently, there are about a dozen articles available...