The first principal, Mr McGregor, ably assisted by his deputy, Mr Unicombe until 1961, started with a small group of teachers and two hundred and seventy-five boys and one hundred and thirty girls, all in First Year.  The girls left at the end of First Year and new groups of boys were admitted.

In 1969, the school had grown to the stage where subject masters were appointed.  Mr Conomy came from Casino High School as Master of English and History, Mr Leeder came from Fairfield as Mathematics Master, Mr Holmes as Science Master came from Port Hacking, Mr Lennon came from Punchbowl as Commerce Master and Mr Stanton came from Lismore as Manual Arts Master.

In 1962, there were eight hundred and thirty-eight pupils, forty-two teaching staff and two clerical assistants.  There was also room for romance - during 1962 and 1964 marriages occurred between staff members.  In 1963, the 'travelling class' idea was introduced in second, fourth and fifth years.  This was an attempt to give the best opportunities to students who were learning different subjects at different speeds, by having class groups change with the subjects.  In the mid-sixties the school reached its peak of one thousand, two hundred students.

Epping was on of the first schools in NSW to provide a Careers Night in 1959 to help students become aware of the careers available to them.

Mr Flynn, the second deputy, left at the end of 1964 after four years at the school and Mr McGregor retired in 1965, thus bringing to an end the first era of the of the school.  During his life time as principal, the school had grown to a community of almost one thousand people.  A few windswept buildings on a bare and barren ridge had become an attractive group of buildings in charming gardens, and he left the stamp of his personality on the school - high moral principles, strict discipline and academic excellence.

In 1966, Mr Williams replaced Mr McGregor.  In the next few years there was an emphasis on the humanities subjects.  There was encouragement of reading among the students and many book reviews appeared in Southern Cross and other school publications.  There were also school spelling championships in four divisions, as well as essay competitions and encouragement of drama, oratory and languages - with six teachers on the languages staff.  Much of this was the result of efforts by Mr Ron Learmonth, the English Master who died during 1969.

In 1971, Mr Williams retired and was replaced by Mr Brown.  Mr Brown guided the school through the next eight years and continued the emphasis on academic and sporting excellence.  He was replaced by Mr Hayes who was in charge for the last two of the school's first twenty-five years.

In 1972, the library was opened.  It was a new design and was quickly absorbed in to the school's daily life.  It also, by providing micro-teaching rooms for Macquarie University, state-wide Library Prefects' Meetings, and teacher inservices, became important in the wider community outside the school.

By the mid-seventies the direction and growth of the school were changing again.  Languages were losing their popularity and only three teachers were involved part-time in that area.  Besides the teaching staff, there were four clerical assistants, three general assistants, two library assistants, two teachers' aides, as well as twenty-four prefects and twenty members of the Students' Representative Council.

In 1977, a new set of subjects was introduced into the school as Other Approved Studies.  These were mainly for year 11 students and the one year courses included Motor Maintenance, Computer Science, Film Making, Physiology of Exercise, Political Economy, boat Building, Basic Radio and Anthropology (for Year 12).

In 1981, a Transition Education class was introduced to assist Year 10 boys who expected problems moving into the workforce.  In the same year the principal, Mr Hayes, broadened the subject offering in the junior school and encouraged staff to develop school-based courses such as Living Skills and Applied Physical Dynamics and Dimensions which were offered alongside the official syllabuses of the Board of Secondary School Studies.