Patrick Moriarty, the headteacher, said: "Both academic and vocational outcomes are testament to the exceptional hard work and dedication of staff and students alike, who were tackling new and demanding specifications in many subjects.
"We are proud not only of the academic accomplishments of our students, but of the qualities that have grown in them during their time at JCoSS.
"They leave as accomplished mensches, embodying the values of the school and the wider community, and ready to act as ambassadors for both as they step forward on the next phase of their journey."
Hasmonean Boys' and Girls' schools, in Hendon, reported that 17 per cent of grades awarded were A*s, and 44 per cent were between A* and As. In mathematics, the school's best-performing subject, almost three-quarters of pupils achieved an A or above.
This year the proportion of pupils getting an A* at A-level in England declined to its lowest level since 2013, Schools Week reported today. Eight per cent of pupils reached the very top grade, down from 8.3 per cent last year.
A quarter of pupils at the fee-paying Immanuel College, in Bushey, achieved A*s and As across the board, while 23 per cent of all grades awarded to the school were A*s.
Headmaster Gary Griffin said: "We are delighted with this year's A-level results at Immanuel College which are even better than last year's, despite the fact that the examinations have been made more rigorous and demanding as a consequence of Government reforms.
"I would like to congratulate the students - and their teachers - who have worked so hard to achieve these magnificent grades which are thoroughly deserved."
Nearly half of all grades at the Europe's largest Jewish school, JFS in Kenton, North London, were A*s or As, and three-quarters were Bs and above.
The school also reported results from its vocational courses, including the CACHE courses in care, health and education, in which all students attained the equivalent of three A*s or As, and the hospitality BTEC, where all students attained double distinction.
Headteacher Rachel Fink said: "We are immensely grateful to our dedicated staff who guided them through the past two years, both academically and pastorally and to our parents who offered so much support."
Nearly a third of pupils from Yavneh College, in Borehamwood, Hertfordshire, got all A*s and/or As. More than half of all grades were awarded at the highest level.
Headteacher Spencer Lewis hailed the "very hard working, dedicated students", as well as his "remarkable team of teachers".
Yavneh College pupil Erin Waks, 18, told the JC she was "shocked" when she opened her results to discover she had three A*s.
She said: “I was not expecting it at all. I was so surprised when I found out. I have spent the whole summer trying not to think about the results and last night I was up every single hour.”
Ms Waks said she wants to go to Durham University to study English and French.
She said: "I’m really interested in academia so maybe after university I will do something like that. I don’t know, but I just love reading. My family are very proud; my dad was up with me since 4am."
King David High School, in Liverpool, reported that 100 per cent of its pupils passed their A-level and BTEC courses.
