The Forest History Society is a nationwide society dedicated to preserving the history of the great forests of the United States. The society puts on yearly lectures and conferences, and also hosts an impressive research center full of primary sources.

The society offers educators sample curriculum, a teacher guide, and an education newsletter. The website offers a history of the society, visitor information, online links to sample curriculum, and back issues of the educational newsletter.

Does not appear to be affiliated with a specific historic site intended for K–12 audiences.

Historic Pittsburgh is an online collection of local historical resources, including materials held by the University of Pittsburgh's University Library System, the Library & Archives at the Heinz History Center, the Carnegie Museum of Art, Chatham College Archives, Pittsburgh History & Landmarks Foundation, and the Point Park University Archives.

The website offers databases of maps, images, and census records. The website also offers library access to the above-mentioned libraries, general historical information, and a page for teachers detailing suggested classroom applications of the website. To contact the site via email, use the webpage: http://www.library.pitt.edu/services/aska.html.

In the summer of 1957, the city of Little Rock, Arkansas, decided to desegregate it schools, setting in motion the turn of events that defined the Little Rock Nine, and included protests, marches, riots, and threats of violence. The Central High School Museum chronicles the history of the 1957, the year of desegregation.

The museum offers visitors copies of the 1957 student newspaper, a variety of exhibits showcasing life inside Central High during 1957, and offers videos and other primary sources from the 1957 school year. The website offers a history of desegregation in Little Rock, as well as an events calendar, a timeline of events in 1957, and visitor information.

It looks like this site no longer exists as a visitor's center and is being renovated. Check back on this one.

Umbrella/professional organization, not a specific site.

The American Folklore Society is an association of people who study and communicate knowledge about folklore throughout the world. The Society's more than 2,200 members and subscribers are scholars, teachers, and libraries at colleges and universities; professionals in arts and cultural organizations; and community members involved in folklore work.

Academic/professional organization, not a historic site.

The National Preservation Institute (NPI) is a nonprofit organization offering specialized information, continuing education, and professional training to those involved in the management, preservation, and stewardship of our cultural heritage. It offers seminars in historic preservation and cultural resource management and serves a broad spectrum of professionals from both the government and private sectors by providing preservation information, knowledge, and skills to train and guide the stewards of the United States' historic and cultural places.

Preservation organization, not an individual historic site.

Through student/teacher workshops, tours, exhibits, and a variety of educational programs, Landmarks encourages people to notice and appreciate historic buildings, parks, public spaces, bridges, streets, and other assets that make up the city and its neighborhoods and compose the character of the Pittsburgh region. Landmarks works to preserve and restore the area's historical assets and to assist others in doing the same.

The foundation offers courses, tours, and other educational and recreational programs.

Seems to be more a preservation/umbrella organization than individual historical sites.