Source: Enter an Archive of 6,000 Historical Children’s Books, All Digitized and Free to Read Online | Open Culture

This collection may be more of interest to history classes versus primary and intermediate classes. The books look really interesting, I really like Elfin Rhymes (mentioned in the article).

Since these books are in the Public Domain, students can do whatever they want with the characters or the graphics. Remix or rewrite, they are no copyright restrictions on the works.