Okla. Stat. tit. 70, § 1210.278

A. The board of education for each school district in the state shall implement a system to provide educational screening as required in this section. B. The service centers are charged with the responsibility of ensuring that educational screening is implemented in each public school in the state for all first grade students in each school year. The service centers shall provide assistance and training to school districts for implementation of effective procedures for educational screening and analysis of the results. C. Second grade through twelfth grade students shall be educationally screened as needed or upon request of a parent, legal guardian, or teacher pursuant to regulations promulgated by the State Board of Education. D. Students entering the public school system from another state or from within the state without previous educational screening shall be educationally screened within six (6) months from the date of such entry. E. No child shall be educationally screened whose parent or legal guardian has filed written objection with the local school district.