History and Philosophy of Mathematics
The History in Britain features 1000 or so biographies. Of interest to advanced students is the use of Java to illustrate and manipulate classic curves. KnotPlot is another knotty site for advanced math students.
The life and times of Galileo is explored in-depth at the Rice University site.Of particular interest is the information about his own laboratory and instruments. Maps, timelines and excerpts from the famous trial are also provided.A very thorough view of the history of this period which could be a model for other studies in later eras. For a 360 degree view of his actual facilities and equipment travel to Florence, virtually.
Cut-the-knot, an award-winning site, explores geometry, algebra, and special topics like probability. Java is used to display and manipulate classical problems. The best aspect of this site is the reflective perspective of its developer and his dose of philosophy of math. (Unfortunately, this sites loads in such a way that sometimes it throws a monkey wrench in the browser so access it during a slow time.)
The history of science is often overlooked in schools so many developments are presented out of context. Traditional Islamic culture contributed many breakthroughs to mathematics and science. See the history review in NSTA.
This collection demonstrates how new tools will change pedagogy.
History and mathematics usually remain quite separate in most curricula. These sites correct that view and by showing the evolution of thought could stimulate students, even below college level, to imagine the next stage in the development of mathematics.