A plethora of videos for teachers to use with students for exploring concepts in multiple subject areas. Some of the videos would be appropriate and some are not - you really need to pre-screen them before using withstudents.

Coolmath has a ton of cool math games and puzzles, lots of really clear math lessons (arithmetic, fractions, decimals, algebra, etc.), fractals, geometry, tessellations and more. Tons of very cool math stuff for kids, teens, parents and teachers too!