The state of Oklahoma has a non-tiered certification system. Teachers, certified to teach in Oklahoma, are required to hold a Standard Teaching Certification.
Qualified applicants seeking certification in a world language that has no state competency examination must obtain a score of at least “intermediate-high” on the exams administered by the American Council on the Teaching of Foreign Languages (ACTFL) in the foreign language for which the applicants are seeking certification: (The Oral Proficiency Interview (OPI) or the Oral Proficiency Interview Computer (OPIc); AND The Writing Proficiency Test (WPT)). Applicants holding a valid Oklahoma traditional or alternative credential may add a world language that has no state competency examination by meeting a testing requirement. The Oklahoma State Department of Education (OSDE) may issue a certification in Native American Languages that have no state competency examination to qualified applicants who demonstrate proficiency in the Native American Language, as determined by a federally recognized tribe or tribal entity.
It is worth noting that the Oklahoma State Board of Education has identified the study of languages (modern, classical, Native American, American Sign Language) as core curriculum along with science, mathematics, social studies, language arts, and the arts (visual art and general music). All districts are required to implement a sequential program of study of at least one language other than English in the curriculum. For additional information about certification, please, consult the Office of Certification at the Oklahoma Department of Education.
This is a list that the state maintains of approved credentialing programs. Use this list to search for credentialing programs that fit your needs. There is a filter function on this list that displays approved language credentialing programs. The state may periodically change this list. Credential-seeking individuals must attend a program from this approved list to receive credentials in the state of Oklahoma
http://teachoklahoma.org/colleges-universities