167.131.  District not maintaining a high school through twelfth grade shall pay tuition and transportation, when — amount charged. — 1.  The board of education of each district in this state that does not maintain a high school offering work through the twelfth grade shall pay tuition as calculated by the receiving district under subsection 2 of this section and provide transportation consistent with the provisions of section 167.241 for each pupil resident therein who has completed the work of the highest grade offered in the schools of the district and who attends an accredited public high school in another district of the same or an adjoining county.

  2.  The rate of tuition to be charged by the district attended and paid by the sending district is the per pupil cost of maintaining the district's grade level grouping which includes the school attended.  The cost of maintaining a grade level grouping shall be determined by the board of education of the district but in no case shall it exceed all amounts spent for teachers' wages, incidental purposes, debt service, maintenance and replacements.  The term "debt service", as used in this section, means expenditures for the retirement of bonded indebtedness and expenditures for interest on bonded indebtedness.  Per pupil cost of the grade level grouping shall be determined by dividing the cost of maintaining the grade level grouping by the average daily pupil attendance.  If there is disagreement as to the amount of tuition to be paid, the facts shall be submitted to the state board of education, and its decision in the matter shall be final.  Subject to the limitations of this section, each pupil shall be free to attend the public school of his or her choice.