In October 1961, the Auditorium was opened with a seating capacity of 600 built at a cost of Rs. 3 Lakhs. The same year the school was upgraded to the Higher Secondary Level (Class XI) and the first batch passed out in 1964. In May 1964, another New Hostel was added across the Football field (the present Boys’ Hostel), the campus was demarcated with two main gates, the upper Gate and the Main Lower Gate, and both built in traditional Sikkimese architecture.