A coalition of private and state schools is expected to launch a campaign to end GCSEs, as growing numbers of schools look at alternatives to the exams following the summer algorithm debacle.

Eton, Bedales, St Paul’s girls’ school, Latymer upper school and several substantial academy chains have been joined by Margaret Thatcher’s education secretary, Kenneth Baker, who created GCSEs, to discuss proposals for replacing the exam system.

The group, Rethinking Assessments, is likely to launch a formal campaign in the next few weeks, forcing ministers into a battle for control of school qualifications.