The Geometry Forum is "An Electronic Community for Lovers of Geometry." An NSF-funded project at Swarthmore College, the Geometry Forum is a great place for geometry and math teachers to locate curriculum ideas, software for mathematics, Internet math projects, and information about professional organizations. The student center offers a problem of the week, project of the month, the Internet...

This Web site provides detailed discussions of Diamond Theory, and is intended for college math students or mathematicians. Diamond Theory, according to the author, is best classified in the subject of "finite automorphism groups of algebraic, geometric, or combinatorial structures." The main focus of the material is the technical aspects of the concept, but there are some references to its...

The Macalester College Problem of the Week (MacPOW) is a tradition that began in 1968 as a fun, challenging activity for freshmen college students. It continues to this day (hosted by the well known Math Forum site), and about 200 problems are archived on this Web site (out of nearly 1,000 total). All of the unique conundrums are mathematically oriented, and most are word problems that require...

Maths Challenge is a fun activity to build mathematical and reasoning skills. Each month during the school year, a new set of math problems are posted online. There are miscellaneous problems at junior and senior levels, cryptography and code breaking problems, and computer programming challenges. Each section is appropriate for a different age range, but the most basic material starts at age...

Problems to Enjoy presents an enormous selection of mathematics problems for middle and high school students. Teachers will find it especially useful; divided into four categories and three grade levels, the problems are easily searchable. Eventually, the site's creators hope to "build up a comprehensive library of problems in a format that is simple to access, download and customize." The...

Proving that geometry can be more fun than a barrel of monkeys, Archimedes Laboratory is "an 'intuitive' puzzle site with fewer formulas and more visuals, which may encourage students learning this science or just constitute a platform for reflection." Probably the most strictly educational section of the site is Math to Discover, which contains discussions of the history of numbers and...

This site departs from the common themes taught in general geometry classes and introduces projective geometry, which has to do with special properties resulting from the intersection of lines, planes, and points. The coincidence of such elements is what is referred to as an incidence, and this is the basis of the topic. The site makes extensive use of animated figures to demonstrate principles...

This is one of the best online resources about fractals, and is "meant to support a first course in fractal geometry for students without especially strong mathematical preparation." The site is incredibly deep, providing everything from the most basic definitions and non-technical discussions to involved mathematical formulations. Interactive Java applets, downloadable software for the PC and...

Science UTM offers online articles and activities "for people who like science." Science U and the web-design and development company that owns and operates the website, Geometry Technologies, were formed as a result of the closure of The Geometry Center at the University of Minnesota. One of the conditions of that grant, which funded The Geometry Center and ended in 1998, was that the Center...

Annenberg/CPB, part of The Annenberg Foundation, develops multimedia resources to help teachers "increase their expertise in their fields and assist them in improving their teaching methods." This section of the Annenberg Teachers Lab features lessons on Shape and Space in Geometry. The website reviews the ways in which geometry is not abstract, but rather is "fun and colorful, instructive and...