JFS, the country's largest Jewish school, has been praised for the quality of its Jewish education by Pikuach, the Board of Deputies-run inspection service.
A report published this week rates the school's Jewish studies as good overall, with a number of outstanding features. Inspectors found "a very positive and healthy climate for learning. Students are in the main interested and engaged."
Pupils' spiritual, moral, social and cultural development was outstanding, as was the curriculum and leadership of Jewish education. More than two thirds - 69 per cent - obtained an A* or A in GCSE religious studies.
Pikuach said this was "a direct result of the Jewish studies department's constant drive towards an upward trend in academic progress and achievement". The informal Jewish education programme, including lunch-and-learn sessions and trips to Israel and Poland, was also deemed outstanding.
The report is a morale boost for JFS after Ofsted inspectors downgraded it from "outstanding" to "requiring improvement" in the summer - although a follow-up visit noted that the school had since made progress.
Pikuach found that students "think deeply about their own and others' experiences and try to relate them to a clear set of personal and Jewish values".
They were encouraged to consider the needs of others through more than 20 charity initiatives.
But some students, particularly in the sixth form, could be achieving more in their Jewish education.
And although JFS tried to ensure that as many pupils as possible participated in an act of daily worship, there was "still further work to be done".
Welcoming the findings, school head Jonathan Miller said: "We have high aspirations for all our students and this includes a wish that they make progress on their individual Jewish journeys.
"It is pleasing that the inspectors recognised that JFS provides a Jewish environment where students are able to make this progress."