The St John's site is still owned by Magdalen College, Oxford, and they are represented on the governing body, but Magdalen (Brackley) had to lease the site from the Oxford college for 999 years to become an academy.

The site now occupied by the school was originally the Hospital of St. James and St. John, founded around 1150 by Robert le Bossu, Earl of Leicester.

By 1548 there was a school at the site, its initial purpose being to allow pupils of the college in Oxford to escape the plague affecting the city at the time.

This school has approximately 1500 students Formerly a chapel for the hospital of St. James and St. John, the earliest datable parts are late-12th century, although many parts are 13th century.

It remains in regular use by the school, Church of England and local community.