http://math.rice.edu/~lanius/frac Fractals. (5/6+) This site has great upper elementary and middle school units on the mathematics of these visually stunning images. This site also include Internet research activities.
http://sprott.physics.wisc.edu/fractals.htm Sprott’s Fractal Gallery. (6-12) INTERACTIVE This site is from Julien C. Sprott. It includes an archive of previous fractals and links to a large number of fractal patterns from other sources. Every day the site present a new fractal that is automatically generated.