Math Tools for Teachers, K-12

http://www2.ups.edu/community/tofu/home.htm
Tools for Understanding is an online professional self-development resource for teachers. The math concepts section provides a wide variety of lessons arranged by topic such as spreadsheet basics, factors, primes and functions, fractions, decimals, percents, geometry, working with data, and more.
The lessons integrate technology (either spreadsheets or calculators) into the learning process and can easily be included in the existing curriculum.
The integrated lessons section provides examples of in-depth problem solving in mathematics and explicit suggestions for moving students through the problem solving process toward high-quality products.
The journaling section explores the idea of writing in mathematics and offers tips for getting started as well as prompts to use, strategies for incorporating writing into the mathematics class, and lesson plans.