This website is a portal for many other websites that would be very useful for teaching. I haven't looked at all of the links, but there are links to major websites like the Smithsonian and Library of Congress, both of which I know have primary documents available on them. Not all of these sites have government documents on them, but many of them do.
This is another portal with a ton of great links. There is a page full of links for educators and then drop down menus that separate K-6 and 7-12. In these drop-down menus are links to entire pages of websites devoted to topics like the government, history, the military, math, and science. Not all of these sites have government documents, but many of them do.
This website has primary sources and government documents on it. It is another portal site with a section devoted just to kids with links to government information, websites of government agencies for kids, a NASA page, and the health pyramid. It also has primary documents on the census dating back to 1790 which I thought was pretty neat.
This website is another portal with many links that are organized very well. This website has 2 links that I would use most often and they are the Ben's Guide to the Government link, which is a very kid-friendly website that talks about the U.S. government, and it has a link to primary early government documents like the Constitution and Bill of Rights, etc. This site may not be as useful in the elementary grades as it would in high school, but the links I mentioned above would be good for 5th and 6th grade students.
The official kid's portal for the U.S. Government. Countless of varieties of sites and links to choose from. Wow! What a tremendous wealth of free, fun and fabulous information. To top it off. a search box is included. This site is definitely one for all kids to use for research of all kinds as well as teachers to search and utilize.
Kids.gov links over 2,000 web pages for kids. There are sites from government agencies, schools, and educational organizations, all geared to the learning level and interest of kids.
The site has separate areas for grades K-5, 6-8 and educators. Links to many school subjects. Fun stuff lists activities on many government web sites-NGA, NASA, NOAA, Smithsonian. Links to state government web sites for kids.