St John the Baptist has a strong and rich history of Catholic Education with the Sisters of St Joseph founding the school in 1935. The school opened 29th January 1935 with 23 children.
St John the Baptist Catholic School was originally run as two independent schools under the auspices of the Sisters of Saint Joseph - one school situated at Keswick, then later transferred to the present site at Kurralta Park, known as Saint Joseph’s. The other was at Plympton (for many years known as St. John’s, Mornington). Later the Junior Classes - Reception to Year 3 were placed at Kurralta Park and Years 4 to 7 were at Plympton with each section having its own Principal.
In the early 1970s the school became part of the South West Region and in 1987 the name of the school was changed to Plympton Parish School, with one Principal responsible for the administration of both campuses.
In 1989 a Commonwealth Government Grant assisted in building a new school at Plympton. This is the time when both schools became one school at Plympton. In 1991 the school was officially opened and named St John the Baptist Catholic School.