American Museum of Natural History (Science tab and then Science News for articles )
American Museum of Natural History Science Bulletins
http://www.amnh.org/sciencebulletins/
Smithsonian
http://www.smithsonianmag.com/?ref=home
Smithsonian's History Explorer
http://historyexplorer.americanhistory.si.edu/
Project Gutenburg
http://www.gutenberg.org/wiki/Main_Page
The Library of Congress
http://memory.loc.gov/ammem/index.html
http://www.loc.gov/topics/index.php
Bibliomania
National Geographic
http://www.nationalgeographic.com/
http://education.nationalgeographic.com/education/
Time for Kids
http://www.timeforkids.com/news-archive/all
Primary Sources on the Web
http://www.eduplace.com/ss/hmss/primary.html
Discovery News
Science search engine
Library of Congress
Virtual Library
Kelly Gallagher- Building Deeper Readers and Writers
http://www.kellygallagher.org/resources/articles_archive.html
Award winning site for Poetry
http://gigglepoetry.com/
100 Speeches
http://americanrhetoric.com/