Okla. Stat. tit. 70, § 70-16-111.1: Supplementary textbooks and materials

The funds allocated for textbooks in Section 16-114a of this

title may be used by a school district for supplementary textbooks

and other instructional materials other than those selected and

placed on the list of textbooks by the State Textbook Committee.

The local textbook committee shall submit a statement to the local

board of education justifying any such selections. For purposes of

this section, "supplementary textbooks and other instructional

materials" shall mean materials pertaining to subjects that are not

reviewed by the State Textbook Committee or materials that support

instruction in the subject matter standards as adopted by the State

Board of Education in Section 11-103.6 of this title that were not

reviewed by the State Textbook Committee.