Mr. Dharama Gunasinghe left Nalanda in 1990 and was succeeded by Mr. D. G. Sumanasekara who at that time was the principal of Mahanama Vidyalaya, Colombo. Mr. D. G. Sumanasekara worked hard to improve curricular and extra-curricular, performance of students. Discipline, Punctuality and Attire became key issues of day-to-day life at Nalanda. This motivation resulted in a huge forward leap in standards of every thing from the morning assembly to the school closure in the evening.
The period also saw the laying of the foundation stone for a new three-story building comprising of 11 classrooms. This, was first put into use during Mr. Edward Ranasinghe’s time. Construction work of the New Language Laboratory.