How Ofsted inspections actually work and what the grades mean

The phone call usually comes around midday. A lead inspector rings the headteacher, confirms basic details about the school, and explains that the inspection begins the next morning. From that moment a school has less than 24 hours before a team arrives to compress its entire story, curriculum, behaviour, safeguarding, staffing, results, into roughly two days of evidence gathering. For an institution whose reputation, admissions numbers and leadership careers can turn on the outcome, the brevity is the point of contention and the point of the design: inspectors are meant to see the school as it normally runs, not as it performs after a term of rehearsal.

Ofsted, formally the Office for Standards in Education, Children's Services and Skills, is a non-ministerial government department that inspects state-funded schools in England under the Education Act 2005. Scotland, Wales and Northern Ireland have their own inspectorates, and most private schools are covered by a separate body, so an Ofsted judgement is specifically an English state-school artefact. The interval between inspections depends on the previous outcome: schools judged weakest are revisited quickly, sometimes within 30 months, while those with strong records can wait years, which is why a glowing report from long ago may describe a school two headteachers removed from the current one.

The core method is the deep dive. Rather than sampling lessons at random, the inspection team, often just two or three people for a primary, more for a large secondary, picks a handful of subjects and follows each one vertically through the school. They start with curriculum leaders: what is taught, in what order, and why. They then visit lessons in that subject, look at pupils' books and work over time, talk to the children about what they remember, and speak to the teachers delivering it. The test is alignment. A school can have an impressive curriculum document, but if the work in books is thin and pupils cannot recall last term's content, the deep dive exposes the gap between paper and practice.

Alongside the dives run the data conversations. Inspectors arrive having studied the school's published results, its Inspection Data Summary Report, attendance and exclusion figures, and the responses parents submit through Ofsted's Parent View portal. Leaders are asked to account for anomalies: why disadvantaged pupils' progress dipped, why persistent absence rose, why a subject's GCSE entries collapsed. Safeguarding is checked separately and functions as a limiting judgement, since a school that fails on safeguarding cannot achieve a positive outcome regardless of how well it teaches. Governors, and for academies the trust, are interviewed about how they challenge leaders, because accountability above the headteacher is part of what is being graded.

What the grades actually are now

For three decades the system revolved around four labels: Outstanding, Good, Requires Improvement and Inadequate. That architecture cracked after the death of headteacher Ruth Perry in 2023, when a coroner found the inspection of her school had contributed to her suicide, and the single-word overall effectiveness grade for state schools was abolished in September 2024. What replaced it, phased in from late 2025, is a report card: separate judgements across a wider set of areas on a five-point scale, with safeguarding reported as simply met or not met. The intent is that a school can no longer be summarised, or condemned, in one word.

The consequences remain hard-edged. A school found to be failing can be issued an academy order by the Department for Education, forcing it out of local-authority control and into a multi-academy trust, and headteachers routinely leave within a year of a poor outcome. House prices near sought-after schools carry a measurable premium partly built on old headline grades, which estate agents quoted for years after the visits that produced them.

Reading a report as a parent

A report records what a small team could verify in two days, weighted towards the subjects they chose to dive into. It says a great deal about curriculum coherence, safeguarding culture and leadership, and rather less about the things parents often care about most: whether the music department is thriving, whether a particular year group is well taught, whether a child with specific needs will be happy. Check the inspection date first, then the areas judged weakest, then what leaders were told to improve, and treat the whole document as a dated snapshot taken through a particular lens. The sharpest question to ask on a school visit is not what grade Ofsted gave, but what has changed since the inspectors left.