Answering questions from students at the school from where he matriculated in 1952, Mukherjee who was given a felicitation recalled that the teachers were strict and on his first day he was quite afraid.
The school was also smaller then and had only two buildings, he said.
"Today I am remembering those days," he said.
He was to give replies to 13 questions from students, but could accommodate only 4 because of lack of time.
Mukherjee told the students that those who could not question him, should not feel disheartened and asked them to send the queries to him, which he would answer.
He was also scheduled to meet two or three school friends, who were present, but could not see them.
The President later went around a permanent gallery at the school on his life and times. It came up two years ago.