Officer Candidate School. A program for college graduates who did not attend a A federal university that provides students an undergraduate degree and the preparation needed to serve as a commissioned officer in the US armed forces after graduation. or participate in Reserve Officer Training Corps. An officer commissioning program that allows students to attend non-service academies (i.e. public and private universities and colleges) where students pursue a bachelor’s degree while preparing for service as a commissioned officer in the military.. Successful program completion results in commissioning as a military officer.