Every few years this question comes up on H-Education, so I suppose it's high time to bring it up again:
Are members of the community aware of large scanned collections of textbooks that are online? The UPitt collection immediately comes to mind https://digital.library.pitt.edu/collection/19th-century-schoolbooks but I was curious if there are others.
I'm especially interested in text books from the early 20th centuy, which would have recently fallen into the public domain.
Falling that, are members aware of lists / directories of textbooks, which would allow researchers to identify titles to order/ILL via worldcat?
I'm aware of the 2005 Directory of historical textbook and curriculum collections by Judy Walker, but that doesn't list individual titles in the collections.
My best thought right now is to use the Stanford & Harvard catalogs to identify titles to ILL, but I hope for a more systematic approach. Suggestions welcome - thanks!