History teachers should check out Northern Illinois University’s digital collections. While some collections focus only on Illinois history, others cover a broad range of topics such as the Mexican-American War and election campaigns (1840 – 1860). Each site offers primary sources, maps, lesson plans, audio files, and other materials. Be sure to take a look at Mark Twain’s Mississippi for a number of interesting resources, such as large collection of videos. In addition, Northern Illinois University provides free access to articles published in the Journal of the Illinois State Historical Society between 1979 and 2006.