September 17, 1787, the delegates to the convention approved the text of the Constitution that would be submitted to the 13 states for ratification.
Observing the day:
Liberty Day Institute helps educate Colorado 5th graders about the Constitution and appreciates volunteers.
Hillsdale College has a link to "Constitution 101" which is an on-line short course that anyone can sign up to take for free (or leave a donation?).
KrisAnne Hall recently started an educational web site, Liberty First University, to teach about the founding documents and the previous historical documents that add to the shape. The video lectures can be digested at your pace. This is a subscription site.
KrisAnne Hall has published several books including some for young people. C-span taped her lecture based on the book Sovereign Duty. Both the book and video are recommended.
See also the In Depth interview for BookTV: