Offers access to U.S. census data since the first census in 1790, including a variety of data analysis options, housed at University of Virginia Library
An incredibly rich resource full of curriculum materials for teaching American history, government, etc. - highlights include American Memory, American Treasures, and Thomas
A rich repository of teaching resources from the Smithsonian, including lesson plans and associated materials related to Art & Design, Science & Technology, History & Culture, and Language Arts