From site:
Calisphere is the University of California’s free public gateway to a world of primary sources. More than 150,000 digitized items including photographs, documents, newspaper pages, political cartoons, works of art, diaries, transcribed oral histories, advertising, and other unique cultural artifacts reveal the diverse history and culture of California and its role in national and world history. Calisphere’s content has been selected from the libraries and museums of the UC campuses, and from a variety of cultural heritage organizations across California…
The collections are searchable by topic, and so make good resources for teachers and students.