At the beginning of the 1970s, Trinity purchased land beside Lake Eppalock, near Bendigo, opening the Leppitt Outdoor Education Centre in 1973, named after the headmaster. In 1975, the boarding house, which had been run in Merritt House, closed after more than 60 years. The War Memorial Library was demolished in favour of a new classroom building, the three-storey Tonge Building, and the library relocated to one floor of the Shann Building. Several years later, in 1979, John Leppitt retired. The new headmaster, Don Marles, continued the development of the school with a new swimming pool in 1980 and the renovation and renaming to the Bright Laboratories of the original science laboratories housed in the Shann Building. Merritt House, the former boarding house, was converted into a music school.