Okla. Stat. tit. 70 § 5-102
All independent school districts in Oklahoma shall be those which shall have maintained during the previous year a school offering high school subjects fully accredited by the State Board of Education.
A reasonable deviation from any of the requirements enumerated herein shall not operate to prohibit the State Board of Education from designating any district as independent if the other requirements are sufficiently superior to the minimum standards required herein, but standards therefor shall be reduced to writing and a copy thereof sent to all districts maintaining high schools in Oklahoma at least one (1) year prior to the time the requirements become effective. Until the effective date thereof, the requirements hereinabove enumerated shall remain in full force and effect. As a basis for attaining the status of independent school district, high schools shall be inspected by a member of the division of secondary education of the State Board of Education or such other representative as the State Board of Education shall designate, and all of the standards prescribed by the State Board of Education shall be carefully checked in the presence of the district superintendent of schools or board of education of the district. A written report shall be made and mailed to the district superintendent of schools and board of education within thirty (30) days after the time of such inspection. Such report shall indicate if the high school meets the requirements and, if not, a statement shall be made as to what must be done in order to comply therewith.
After any school district has become independent, it shall remain so until removed from independent status by the State Board of Education, which, however, shall not remove any school district from independent status until it is satisfied that the minimum standards for independent school districts are not being maintained. Any order of the State Board of Education removing a school district from independent status shall not become effective until the close of the fiscal year in which such order is made, and any order removing a school district from independent status which has heretofore been made by the State Board of Education, regardless of notice or effective date thereof, is hereby validated. A reasonable variation from year to year in the minimum number of teachers required shall not affect the status of any independent school district.
Okla. Stat. tit. 70, § 5-102