Some of these sites are design for AP Statistics Students. However they contain excellent content for any statistics student.
University of Rice
Many other Sites to pick from (page not available)
Data and Story Library - DASL
StabLib at Carnegie Mellon University
Bureau of Census
National Center for Education Statistics - US Dept of Ed
Data Sets and References from St. Lawrence University
University of Florida: Links to Many other Resources (University Depts, Associations, etc.
USA Counties 1969-1994 in Map Format at Oregon State U. Gov. Info Sharing Project
Save the Manatee Club
The American Statistical Association