Okla. Stat. tit. 72, § 304

Each qualified veteran shall be entitled to one (1) month's tuition-free schooling for each month of active duty service between the dates of August 10, 1964, and December 31, 1976, with a maximum of thirty-six (36) months tuition-free schooling. Time spent in reserve status with the Oklahoma National Guard or various other reserve components of the United States Military shall not be considered as active duty time. Laws 1974, c. 181, § 4, emerg. eff. May 14, 1974; Laws 1979, c. 96, § 2, emerg. eff. April 24, 1979.