Like snopes.com which debunks internet myths, this site provides evidence for what is and what is not in the constitution. For instance, did you know that nowhere in the Constitution does it enunciate the right to trial by a “jury of one’s peers”?
Another phrase commonly attributed to the Constitution, “We hold these truths to be self-evident, that all men are created equal”, actually comes from the Declaration of Independence.
It also has information on the Magna Carta, the Emancipation Proclamation, the Gettysburg Address and many other historical American documents.