My Dynamic Geometry Sketches have been updated with a really cool interactive Java sketch "Finding the median and centroid of a triangle by experimentation: A gravity simulation." at http://math.kennesaw.edu/~mdevilli/findingtrianglemedian.html

 Another new Exploration for Students "Area ratios of inscribed polygons" and several other explorations can be found at:

http://math.kennesaw.edu/~mdevilli/studentexplore.html 

And at the bottom of the Main Page at http://math.kennesaw.edu/~mdevilli/JavaGSPLinks.htm

a link has been added for doing "Turtle Geometry" online.

Lastly, for those interested in the Van Hiele theory and its implications for teaching & learning geometry: my homepage at http://mysite.mweb.co.za/residents/profmd/homepage4.html
has under Math Ed articles been updated with a 1987 RUMEUS report "Research evidence on
Hierarchical Thinking, Teaching Strategies and the Van Hiele Theory: Some Critical Comments"