Quay Academy, in Oxford Street, was told it requires improvement in four of the five assessments.
Provisional results in 2017 show that the school has performed less well than in 2016 in key stage one and two.
Pupils’ progress was below national figures with 56% of Year 6 pupils achieving the expected standard of reading, 60% in writing and 70% in mathematics.
The report also said: “Disadvantaged pupils are making less secure progress than other pupils.”
Children’s personal development is good and pupils talked confidently about how to keep safe. The school, run by the David Ross Academy chain, was also told behaviour of pupils needs to improve.
The report revealed that although the vast majority of pupils are well behaved, the behaviour of a significant number of boys is spoiling learning times for others.
Adding: “Pupils say that a small number of pupils use derogatory, sometimes homophobic, language, although adults check this when they hear it.”
Inspectors, who visited the school on September 26 and 27, found there was a lack of consistency in the quality of teaching.
Phonics has not been taught effectively. And in some key stage 1 classes, pupils are making less progress in writing because they are struggling to sound out new words and to form letters correctly. In fact, the number of pupils achieving the Year 1 phonics check went down from 2016 to 2017 to 10% below the national average.
The school did, however, receive a ‘good’ rating for its early years provision.
The report said: “Teaching is effective in supporting children to develop knowledge and understanding in number and to develop their use of language.”
Kimberley Lawton, principal at Quay Academy, said: “Following our recent Ofsted inspection, we have taken on board inspectors’ comments and have a clear plan of action in place.
"As part of the David Ross Education Trust, we are committed to providing a world-class education for each and every one of our pupils, and we are confident that Quay Academy will continue to make rapid progress.”