The Calcutta Boys’ School, established by Bishop Dr James Mills Thoburn of the Methodist Episcopal Church in1877, initially started on the rear veranda of the Thoburn Church Personage, located on Dharamtalla Street, opposite to the site of the Methodist Episcopal Church. After some time, it was housed in a room in the massive building of the Whiteaway, Laidlaw & Co, located at the intersection of the Jawaharlal Nehru Road and SN Banerjee Road. After the initial days of struggle, the school could finally settle at its present site on SN Banerjee Road, mainly due to the generous donation of Sir Robert Laidlaw, the founder-chairman of the great business houses Whiteaway, who donated a big plot of land and arranged for the construction of the Main Building in 1893 and the Renfrew House in 1902.
Sir Laidlaw, regarded as the chief patron of the school, subsequently endowed the institution with three magnificent Waverly Mansions in 1903 and established the Calcutta Boys School Endowment Trust in 1904.
During its early days the school had to struggle hard for finances and was on the verge of closing down during the Great Depression, when Horace Christopher Fritchley took the complete responsibility and saw the school through the turbulent days. In fact, he dedicated his life for the betterment of the school and after retirement donated his retirement benefit and gratuity to his dear CBS, which later helped the construction of the Middle Building in 1962 and named Fritchley Building, to commemorate his dedicated service for more than 40 years as a teacher and the Principal of the Institution.
He was succeeded by his son-in-law, Clifford Hicks in 1952, who took voluntary retirement from his position of Principal and Secretary in October 1974. The school library was named after him as the Clifford Hicks Memorial Library.
The Calcutta Boys’ School is an English medium Christian day school for boys managed by the Calcutta Christian Schools Society and is recognized by the Government of West Bengal through the Deputy Director of School Education, Anglo-Indian Schools. It is affiliated to the Council for the Indian School Certificate Examination (CISCE), New Delhi and prepares students for the Indian Certificate of Secondary Education (ICSE) examination and Indian School Certificate (ISC) examination. However, from the nursery section to class VIII, the curriculum prescribed by the Interstate Board of Anglo Indian Education, New Delhi is followed.
The school has four houses, which are named after the founder, benefactors and well-wishers of the school as, Thoburn (Red), Laidlaw (Green), Warne (Yellow) and Henderson (Blue).
Students are always encouraged to take an active part in the extracurricular activities such as quiz, debate, plays, Eastern and Western music. The school is equipped with a playground and has an Interact club which runs social projects and sports activities like, football, cricket, karate and athletics.