Constitution Day

United States Constitution

Articles of Confederation (FindLaw): Full text of the first Constitution, effective 1781.
Constitution (via Cornell Law School): Original text of Constitution with hyperlinks to amendments.
Constitution of the United States Annotated (GPO Access): Constitution and Amendments annotated with references to Supreme Court cases as of 1992.

Debates in the Several State Conventions on the Adoption of the Federal Constitution: Debates and background materials on the adoption of the Federal Constitution in the State Conventions. Searchable and browsable by state.
Documentary History of the Ratification of the Constitution and the Bill of Rights: Slavery (Univ. of South Carolina): Text of the slavery debate during the ratification of the Constitution. Primarily newspaper excerpts from the period.
Federalist Papers: Letters and news articles written by Jay, Hamilton and Madison on the provisions of the Constitution. Used widely for interpretation of the Constitution. Searchable and browsable.
Anti-Federalist Papers: Calls for major revisions.
FindLaw Constitution Law Center: Detailed annotations on legal cases interpreting each article and amendment to the Constitution. Includes Articles of Confederation and biographies of Founding Fathers.
Records of the Federal Convention: Plans and letters as well as notes taken by James Madison at the Constitutional Convention of 1787.

Constitution Day (National Archives): View high resolution scans of the original, signed Constitution; obtain a transcription of the document; read an essay about the Constitutional convention; learn dozens of fascinating facts about the Constitution; find out about the 39 delegates who signed the Constitution on September 17, 1787.
Current Events in Context: Constitution Day (CQ Press): Site contains lesson plans for teachers, background histories about the Constitution, governmental powers, Pro/Con debates on Constitutional issues from The CQ Researcher and more.
Professor Dave Rausch's Constitution Day Web Site: Dr. Rausch and his wife, Librarian Mary Rausch, have put together a great list of links for Constitution Day.