Situated in Hornby Street, the school was officially opened on 1st September, 1877.
It was to be the most eagerly awaited education facility in the area and was a forerunner in many things. It was opened as Prahran South, but was renamed Windsor in 1891. In 2001, it became known as the Stonnington Primary School.
The original single storey building cost £4,220.7.11. The Hornby site was purchased for £1,300. During the first year, the total enrolments were 716. For many years an old house on this site served as the accommodation for the Head Teachers from both Windsor and East St. Kilda. Nine teachers were employed during this time; approximately one teacher to every seventy students. From its earliest years the school suffered overcrowding and during 1880 and 19915 various temporary premises had to be used.
Amongst these premises: St Matthew’s Church, Prahran Salvation Army, the local Baptist Hall in Albert Street and a factory hall in Duke Street. It was in 2890 that the second storey was built over the central wing of the original building, to enlarge the premises.
By 1912, overcrowding was still a problem and further re-modelling consisted of a two storey wing in 1915. At this time 501 pupils attended the school and with the development of flats in the area and an influx of migrants in the 1960’s, six new classrooms were added. In 1973, the peak enrolment was 787 due to the large influx of migrants and the development of housing in the area.
Throughout the school’s history the committee has maintained a close contact with local members of Parliament and many achievements have come about as a result of this direct representation. In 1905, the most prominent of Head Teachers was Thomas Gray, who was born on the Ballarat goldfields. He refused promotions, staying at the school until 1919 and was responsible for many achievements during this time. These included better ventilation, smaller class sizes, better conditions, establishment of flower and vegetable gardens, woodwork and occupational therapy groups for War Veterans. He taught geography and had the entire world map painted on the school grounds.
In many ways, Windsor Primary School led and paved the way in school development. At the turn of the century, the school sold meals prepared by the students to cover running costs. It was one of the first in the state to open a canteen. In 1967, thanks to a committed school council, the school led the way once more by opening a multi-purpose room, fully equipped with television, projector, seating and kitchen facilities.