Section 10. If the school committee of a town of less than five hundred families or householders not maintaining a public high school offering four years of instruction, pays, with the approval of the department, for the instruction of a pupil who by reason of physical disability is unable to attend a high school in another town, the commonwealth shall reimburse the town therefor under the same conditions and to the same amount as for tuition in such a high school, and for transportation thereto, but not exceeding one hundred dollars a year in lieu of tuition plus one dollar and fifty cents per week of actual instruction in lieu of transportation.