Prior to 01.10.1970, the post of Secondary Grade Teacher, Primary School Headmaster and Middle School Headmaster were all equal in rank bearing the same scale of pay. In 1971, when the Government implemented the Tamilnadu Revised Scale of Pay Rules, separate scale of pay was fixed for the post of Headmaster Middle School with effect from 02.10.1970 and thus, two separate cadres namely Secondary Grade Middle School Headmaster and Middle School Headmaster came in to existence. After 01.10.1979, B.T. Grade Middle School Headmaster was introduced with an additional qualification of B.T/B.Ed/Tamil Pulavar with a higher scale of pay that of Secondary Grade Middle School Headmaster. As per the Special Rules for the Tamilnadu Elementary Education Subordinate Service Rules, issued vide G.O.Ms.No.1383, Education PUS-I Department, dated 23.08.1988, the B.T. Grade Middle School Headmaster were placed under Class-I and Category – I having the highest scale of pay in Elementary Education up to the V Pay Commission.