U.S. Marine Corps
The United States Marine Corps acts as the initial military respondent, via air or sea, to international disaster scenes and threats to U.S. interests.
Compared to the other four military branches, the Marine Corps history offerings are decidedly limited. However, a small selection of resources may be relevant for K-12 education.
A interactive timeline breaks the history of the Marines down into periods under different leaders, major innovations, and battles in which the corps has participated. The official site also offers back issues of Marines magazine, beginning with 2005.
If you are interested in the social history of the Marines, brief descriptions of their major symbols and lore are the best resources available. Note that some features are covered in both sections.
A national museum of the Marine Corps also exists in Triangle, VA, if a field trip is in store. Tours are not offered, but the website does make gallery worksheets available.