College textbook costs have risen dramatically since the late 1970s. Open educational resources (OERs) stand as a low- to no-cost alternative. This research examined the impact of OER book adoption on indicators of student performance and perceptions of the instructor, learning, and out-of-classroom communication. The first study compared student course grades and persistence before and after an OER book adoption. The second study focused on student perceptions related to the OER book, course instructor, cognitive and affective learning, and student out-of-classroom communication. Results indicated that OER book usage is beneficial to student learning. Implications impacting both instructors and students are discussed for OER adoption in college classrooms.