http://mathforum.org/isaac/mathhist.html   Famous Problems in the History of Mathematics (6-12).   This site presents a collection of great problems that have inspired mathematicians; they are suitable for middle school and high school math students.  Solutions are included as well as links to mathematician’s biographies and other math history sites. 

http://www-history.mcs.st-andrews.ac.uk/history  MacTutor History of Mathematics Archive (6-12) INTERACTIVE.  This archive features more than 1,500 biographies of mathematicians, with snapshots arranged in alphabetical and chronological lists.  This site also includes chronology of important dates, mathematicians who were born or died on each day, birthplace maps, history topics, an index to female mathematicians, and related Web resources.