Free, open source textbook from OpenStax.org. The book offers a comprehensive treatment of core concepts, grounded in both classic studies and current and emerging research. The text also includes coverage of the DSM-5 in examinations of psychological disorders.
MIT Open Courseware has 29 Undergraduate courses in Psychology and 18 graduate courses. Course formats vary, but some include, lecture videos, activities, assignments, discussions, and online resources for further study.