"We the people of the United States, in order to form a more perfect union, establish justice, insure domestic tranquility, provide for the common defense, promote the general welfare, and secure the blessings of liberty to ourselves and our posterity, do ordain and establish this Constitution for the United States of America."
Today, September 17 is Constitution Day. Constitution Day commemorates the formation and signing of the U.S. Constitution by thirty-nine brave men on September 17, 1787, recognizing all who, are born in the U.S. or by naturalization, have become citizens. (source)
Take some time today and revisit the U.S. Constitution. You can see the images of the document on the National Archive webpage
Other resources are:
The Constitution Day webpage
The National Archive Teachers webpage.
The White House webpage
The Library of Congress webpage
The U.S. Courts webpage