Created by Alexander Bogomolny, this site is a clearinghouse of fun and engaging mathematics exercises, puzzles, and other such activities that teachers can utilize in their classrooms. Of course, students might happen across the site and they might become math converts along the way. First-time visitors might wish to read Bogomolny's "manifesto" for the site, and then they can dive right into the material offered here. The offerings are divided into a number of sections, including "Visual Illusions", "Algebra", and "Probability". One particularly nice feature of the site is that many of the exercises and activities here are accompanied by helpful Java applets that include charts, graphs, and other such dynamic elements. Finally, visitors shouldn't leave without visiting the "Mathematical Droodles" section as it's both engaging and thought-provoking.