"Open Educational Resources" by Ron Mader is licensed under CC BY 2.0
OER are teaching, learning, and research resources that reside in the public domain or have been released under an intellectual property license that permits their free use and re-purposing by others. ~ William & Flora Hewlett Foundation
For a more comprehensive overview on OER, see:
"Geography" by slon_dot_pics is licensed under CC
Below are a few OER Geography course materials available. The ACC Libraries' Open Educational Resources Guide as well as websites such as Open Geography Education list additional Open Educational Resources in Geography.