The John Warner School is an academy converter in Hoddesdon, Hertfordshire, admitting pupils aged 11-18. It has a sixth form offering post-16 education. It is part of DANES EDUCATIONAL TRUST. The school has approximately 821 pupils on roll, of whom 19% are eligible for free school meals.
In 2025, pupils achieved an Attainment 8 score of 40.8, placing the school #68 in Hertfordshire and #2,439 of 3,216 nationally. 32.50% of pupils achieved grade 5 or above in English and Maths. 11.6% of all GCSE entries were graded 9–7.
The sixth form offers 15 A-level subjects. 21.9% of A-level entries were graded A*–B, with 1.0% at A*–A. A-level value added: +0.11 — students made above-average progress at sixth form.
Ofsted last inspected the school in 2022. The school's current overall rating is Inadequate. Inspectors assessed quality of education as Requires improvement, behaviour and attitudes Inadequate, personal development Inadequate, and leadership and management Inadequate.
In the most recent admissions cycle, applications were at 0.5× capacity.
The pupil-to-qualified-teacher ratio is 15.9:1. There are no current teaching vacancies.
In the 2024/25 academic year, there were no permanent exclusions. The average suspension rate was 10.4 per 1,000 pupils per term.