Here are some places that might help you find good or interesting history information.
Elm4you - see the link to the right in the gray box "Teens:Grades 6-12"
Check out the Encyclopedia Britannica, Discovering Collection, Info Trac Student edition for starters.
Federal Resources for Educational ExcellenceYou will have to "dig" into some databases here but it is fun exploring.Smithsonian ImagesUncle Sam's PhotosCollection of "free" or not copyrighted photos for you to use.Picture HistoryHistory Day topics from the National Archives
Again, a site you will have to explore.