Section 9. The department, with the cooperation of any town applying therefor, may provide for such instruction in the use of English for persons eighteen years of age or over unable to speak, read or write the same, and in the fundamental principles of government and other subjects adapted to fit for American citizenship, as shall jointly be approved by the local school committee and the department. Schools and classes established therefor may be held in public school buildings, in industrial establishments or in such other places as may be approved in like manner. Teachers and supervisors employed therein by a town shall be chosen and their compensation fixed by the school committee, subject to the approval of the department.