Ben's Guide to U.S. Government for Kids (GPO)

URL: http://bensguide.gpo.gov/

Describes federal government for grades K-2, 3-5, 6-8, 9-12, and teachers/parents
Describes the nation, historic documents, branches of government, national v. state authority, how laws are made, elections, and citizenship
Pleasing graphics, a glossary, games and activities