(1) ¹[Within three years] from the date of commencement of this Act, the appropriate Government and the local authority shall ensure that the Pupil-Teacher Ratio, as specified in the Schedule, is maintained in each school.
     (2) For the purpose of maintaining the Pupil-Teacher Ratio under sub-section (1), no teacher posted in a school shall be made to serve in any other school or office or deployed for any non-educational purpose, other than those specified in section 27.