A bit late but nonetheless, I want to post this link to the government’s site observing the event.
On September 17, 1787, the delegates to the Constitutional Convention met for the last time to sign the document they had created. The National Archives and Records Administration celebrates this important day in our nation’s history by presenting the following activities, lesson plans, and information. We encourage teachers and students at all levels to learn more about our Constitution and government.
The U.S. Senate’s page on Constitution Day is here.
Here is a link to the Constitution. I urge you to read it.
Finally, this page is a great resource with the founding documents available for review.