School Affiliations

St Mary’s school is affiliated to several organisations, which enables us to share expertise with other high achieving, like-minded schools.

Girls’ School Association

St Mary’s is a member of the Girls’ School Association (GSA), which represents the heads of many of the UK’s top performing independent day and boarding schools. The GSA has an international affiliate membership and is a member of the Independent Schools Council. Membership of the GSA enables St Mary’s to stay in the forefront of girls’ education. For more information, please visit

Independent Schools Association

St Mary’s is a member of the Independent Schools Association (ISA) which is is one of the oldest of the independent schools’ organisations. ISA provides access to a wide range of membership services, with our pupils being able to enjoy an extensive programme of local and national Sporting, Arts and Cultural events. Professional support is accessible, with training opportunities available to further enhance all that is offered at St Mary’s. For more information, please visit

Round Square

St Mary’s is a Global Member of Round Square. This is a prestigious network of 180 schools in 50 countries, all of which take a holistic approach to education, based on six ‘Ideals of Learning’ – Internationalism, Democracy, Environmentalism, Adventure, Leadership, Service – first put forward by the German educational philosopher Kurt Hahn in the 1960s. Membership of the Round Square network offers St Mary’s a framework for excellence and continuous improvement, as well as opportunities to collaborate and share experiences with like-minded peers around the world. For more information visit

Independent Association of Prep Schools

St Mary’s Lower School is a member of the Independent Association of Prep Schools (IAPS), which has around 650 of the world’s leading prep schools in membership. Schools must reach a very high standard to be eligible to join, with strict criteria on teaching a broad curriculum and maintaining excellent standards of pastoral care and staff professional development. All IAPS member schools are committed to delivering an excellent, well-rounded education.

Other affiliations

St Mary’s is also recognised as an Ambassador Eco-School, an International School, a National Healthy School, and has Anti-bullying Ambassador Status and holds the Artsmark award.

Our Locations

St Mary's Colchester
Two St Mary's Lower School pupils sitting in a Library holding books and laughing
Additional places now available

Due to increasing demand at St Mary’s, additional places are now available from September.


Enquire today to find out more: