Check out these openly licensed titles. Open Educational Resources are remixable, revisable, and redistributable, and as such, are ideal for curating culturally inclusive and diverse perspectives in course materials that support equitable learning.
Open Access books are free to use, but are NOT remixable or revisable. These are good resources for affordable course materials to adopt "as is".
Check out these links for lesson plans, activities, modules, and assessments. These materials can be interactive, simulations, case studies, oral histories, images, and videos among others.