An organization dedicated to the study of American history has created an extensive collection of resources for teachers.
The Gilder Lehrman Institute of American History, founded in 1994 to promote historical knowledge, posts lesson modules on more than 20 major topics in American history. Each includes a background essay, primary source documents, visual aids (i.e., maps), and learning tools.
The site also includes American history quizzes, an archive of important historical documents, and online exhibitions. The site currently features a multimedia exhibition on war letters, including audio readings and images of original documents.
Partners of the Gilder Lehrman Institute include the Association of Teachers of Social Studies, the National Council for History Education, and the National Council for Social Studies.