(1) A pupil attending public school or the nearest state approved nonpublic school available, to which nonpublic school the pupil may be admitted, shall be transported along the regular routes as determined by the board to public and state approved nonpublic schools. Transportation to public and the nearest state approved nonpublic school located within or outside the district to which nonpublic school the pupil is eligible to be admitted shall be provided under the rules promulgated by the state board. Rules shall not require the transportation or payment for transportation for nonpublic school pupils on days when public school pupils are not transported.

    (2) This section shall not be construed to require or permit transportation of pupils to a state approved nonpublic school attending in the elementary grades when transportation is furnished by the school district for secondary pupils only, nor to require or permit the transportation of pupils to a state approved nonpublic school attending the secondary grades when transportation is furnished by the district for elementary pupils only.

    (3) Vehicles used for the transportation of pupils shall be adequate and of ample capacity.