GCSE results at Ysgol Glan Clwyd have improved this year with 98 per cent of pupils achieving five or more A*-C grades.
Year 11 pupils at the St Asaph school are celebrating the results, the best in its history, which headteacher Martin Davies said improves the high standards of previous years.
Almost a quarter of students achieved five or more A*/A grades or equivalent while 88 per cent of pupils achieved the Welsh Baccalaureate Intermediate Award.
Mr Davies said: "The majority of the main indicators are way above local and national averages.
"We are very pleased once again to see so many young people succeed – it is a tribute to their hard work and determination, the commitment of staff, and the support of parents.
"The challenging targets that were set for this year group as a whole have been exceeded and many have achieved a raft of A* and A grades.
"The pupils in this year group have worked diligently and co-operated happily with staff and fellow pupils, and have succeeded in drawing the best out of themselves and each other.
"They have also been fully supported by the school’s pastoral and mentoring schemes."
A total of 66 per cent of the pupils achieved the level 2+ threshold, achieving equivalent to five or more A*- C grades, including Welsh or English and mathematics.
A large percentage intend returning to school to follow A level courses within the Dyffryn Clwyd Consortium.