Siteseen
Siteseen: American Historama: Hartford Convention 1814
Comprehensive resource provides details of the secret meeting of Federalists in Hartford, Connecticut.
Utah State University
American Journey: Comparison of Articles of Confederation and the Constitution
Two informative charts, one of which compares the Articles of Confederation and the Constitution, the other which lays out the positions of the Federalists and Anti-Federalists concerning the Constitution.
iCivics
I Civics: Race to Ratify
This simulation game set in the 1780s focuses on the ratification of the Constitution.