U.S. Archives and Digital Collections
Try these first:
Annals of American History (Encyclopædia Britannica)
Primary source documents, multimedia clips more »Britannica School High
Encyclopedia articles, high school students more »Catalog of U.S. Government Publications (CGP)
Finding tool for electronic and print publications from the U.S. government more »FDsys (GPO's Federal Digital System)
federal government publications; formerly GPO Access more »