Here are some open resources you might want to use to supplement or, if it is robust, replace a textbook. While many sources are peer-reviewed, please check the source for quality. If you have additional sites to recommend, please let us know!
A textbook appropriate for an Art Appreciation course. Written by Pamela Sachant (University of North Georgia), Peggy Blood (Savannah State University), Jeffery LeMieux, (College of Coastal Georgia), and Rita Tekippe, (University of West Georgia)
This Music Appreciation textbook was created by the following Gwinnett College faculty: Todd Mueller, Elizabeth Whittenburg Ozment, Irina Escalante-Chernova,
Marc Gilley, Catherine Kilroe-Smith, and Rachael Fischer