Nagendranath joined the 'Bhagabati Vidyalaya' at Birsingha village, appointed as the headmaster of the institution established by
Ishwarchandra Vidyasagar for female education, but he left after a short time. It is reported that at the time the institute was a mere mud thatched and straw-shedded hut. One Nabagopal Das, the SDO (Sub-Divisional Officer) of
Arambagh Subdivision arranged for his joining as the headmaster at Arambagh High English School, where he served for the rest of his career, spanning more than 40 years. There is an incident with a school inspector which merits description as it fully shows his in-depth knowledge of grammar. The story goes "once an inspector came to his school and observed him teaching English grammar to the students. Chattopadhyay used the term 'averse from' instead of the
Nesfield style 'averse to'. Shocked, the inspector openly challenged him. To his disbelief, Chattopadhyay pulled out from the library the treatise of Rosewood indicating that it advocates 'averse from'. He also presented with the arguments indicating his grammatical sense was extraordinary." The inspector was awed by Chattopadhyay. He also worked on society problems and in one occasion, received a silver medal and a silver engraved stick from the Bengal government due to his part in successfully observing the 'Water Hyacinth Day' in Teghory Basantapore nearer to Arambagh in the Kana Nadi. == Administrative career ==