Located at 17 Lansdowne Road (now Sarat Bose Road), St. John’s Diocesan Girls' Higher Secondary School is one of the oldest educational institutions for women in Calcutta. In 1876, British missionary Sister Angelina Margaret Hoare from Kent in England started the school with only 16 female students on its roll. Sister Angelina, a kindhearted woman, devoted her life to the advancement of women's education in British India. Nevertheless, the school was named St John’s Diocesan in 1894, by the Clewer Sisters of the convent of John the Baptist from Windsor, Berkshire. It is a Christian school and even today, the Protestant Church of North India runs it.

It is interesting to note that, from 1908 to 1931, St John’s Diocesan was the only Christian women's college of good repute in eastern India. However, the British Government stripped it of its college status, when Bina Das, a student of the school and a member of Chhatri Sangha, a semi-revolutionary organization in Calcutta, fired five revolver shots at Governor Stanley Jackson, in a failed attempt to assassinate him in the Convocation Hall of the University of Calcutta, on 6 February 1932.

From its inception till the 1970s, it was a co-educational institution. However, after that, the school has devoted itself to the betterment of female education only. Today, with more than 3,800 female students, it is often considered as one of the most prestigious girls' schools in the city and is affiliated to the Board of Secondary Education and Council of Higher Secondary Education of West Bengal.

The campus of the school is a mixture of natural beauty along with the original old buildings of the British period and new buildings constructed later. It has two separate playgrounds, one for the students of nursery classes and the other for the seniors. There is a small park within the compound of the school, along with three playgrounds, a basketball court and seven buildings in a lush green surrounding. The school is also equipped with a small chapel, inside one of the buildings.

Each student of the school belongs to one of the four houses, formally known as Rose (pink), Lily (blue), Pansy (yellow) and Lotus (green). Later, the name of the houses and their colours were changed to Angelina Margaret Hoare (pink), Sister Mary Victoria (blue), Sister Hilda Francis (green) and Bina Das (yellow).

The school is equipped with seven laboratories for different science subjects, Home Nursing, junior and senior school computer labs. ‘La Sale Diphony’, the school Music and Audio-Visual room, is also used for conference and seminars. Different musical instruments, like piano, organ, keyboard, guitar and drums are taught in the school. With a seating capacity of 200 students, ‘Dio Bibliothique’, the school library has a wonderful collection of more than 25,000 books. Apart from that, the school always encourages the students to be involved in social services, charities and community welfare.

The school has a rich history of distinguished alumni, which include among others, Lady Abala Bose, wife of Sir Jagadish Chandra Bose, former chief of Army Staff of India Joyanto Nath Chaudhury, former Air Marshal of the Indian Air Force Subroto Mukherjee, Gayatri Chakravorty Spivak, Professor in English, Colombia University, author Maitreyi Debi and Leela Majumder, film director Goutam Ghosh, actor Sharmila Tagore and Mala Sinha.