The superintendent of public instruction and the state auditor jointly, and in cooperation with the senate and house committees on education, shall conduct appropriate studies and adopt classifications or revised classifications under RCW
28A.505.100, defining what expenditures shall be charged to each budget class including administration. The studies and classifications shall be published in the form of a manual or revised manual, suitable for use by the governing bodies of school districts, by the superintendent of public instruction, and by the legislature.