Corby Business Academy has been told it must improve after an inspection by Ofsted.
The school in Gretton Road has dropped from ‘good’ to ‘requires improvement’ after the visit by the education watchdog in November.
A new report says pupil progress is below the national average, the quality of teaching across the school is not consistently good and pupils’ behaviour was not good.
The report also found that sixth form outcomes are not good enough, school leaders have an overgenerous view of the school’s strengths and pupil attendance requires improvement.
However, the report did highlight the school’s support and care for pupils and provision for pupils with learning difficulties as being good.
Executive principal John Henrys said the school would work hard on improving areas identified as needing work.
He said: “Although we must accept the overall outcomes of this report it is disappointing that the Ofsted framework was not able to recognise the improving trend since opening and also the improving predictions over the next three years.
“We will continue to work hard, particularly in the key topics identified, and are confident that the improvements already implemented, together with our high expectations and continuing momentum, will rapidly narrow the gap between our performance measures and Ofsted’s expectations.
“Our committed and hard working staff will continue to put our students’ needs and aspirations at the heart of everything we do.”
The mixed-sex school currently caters for 1,086 pupils.
The Ofsted report read: “Leaders do not have high-enough expectations of what pupils should be able to achieve and they have not taken effective action to improve the progress of pupils across a wide range of subjects.
“Improvement plans are not detailed enough to accurately address the areas in need of immediate improvement.
“There is too much emphasis on completing activities rather than learning from them.
“A lack of purpose and a lack of challenge encourage pupils to lose focus which leads to low-level disruption.”
In August, more than 90 per cent of pupils achieved A* to C grades at GCSE.
To read the full report, click here.