Dawn Spence, headteacher at Argoed High School near Buckley paid tribute to the "outstanding" performances by pupils.
"Our A*-A figures are very impressive and there were some excellent outcomes for our pupils studying GCSEs in drama, French, art and Welsh with each of these departments achieving 100 per cent passes at A*-C," she said.
"The most important indicator is the A*-C including English and Maths and we are delighted that over three quarters of our pupils gained this, while 100 per cent of our pupils achieved 5 A*-G grades.
"We were delighted with the achievements of our pupils and we had no pupils leaving without qualifications, supporting the school’s inclusive approach to examinations.
"I would like to thank the pupils, staff and parents and carers who worked so hard to achieve these results.
"They are up there with the best results we've ever had."
Also celebrating record breaking results was Buckley's Elfed High School.
Headteacher, Rosemary Jones said: "This is easily the best set of results we've ever had - phenomenal.
"We have improved year on year since 2007 and we are five per cent up on last year.
"It is a great way to celebrate the school's 60th anniversary.
"These excellent results are a credit to the pupils, their teachers and their families."
Pupils excelled across the curriculum, with 89 per cent achieving five or more A*-C grades.
Every pupil in the year group gained a GCSE qualification and 100 per cent also achieved five or more grades at A*-G.
Year 11 pupils at Holywell High School were another cohort raising the bar after achieving best ever grades.
All of the pupils leave with five A*-C qualifications and the school also realised a significant 11 per cent improvement in A*-C, with science results improving by a tremendous 44 per cent.
Pupils, parents and teachers celebrated the fantastic achievements of all Year 11 pupils.
Top performing pupils included Ellen Boote, with nine A* and A grades, Jack Foulkes, who got eight A* and A grades and Victoria O'Neill, with seven A* and A grades.
John Weir, acting headteacher at Holywell High School, said: "We are immensely proud of the achievements of all our pupils and we are really happy that so many of them are planning to return to our sixth form next year."
"With the preliminary work on the new Holywell High School building already underway, our sixth form and year 11 pupils have paved the way for us to continue our ongoing improvement and ensure that when we move into our new 'state of the art' school building, the foundations for academic excellence will already be embedded."
The school has seen results rise by six per cent on the previous year.
Julie Price, examinations officer at the Queensferry school, said: "This a fantastic achievement and reflects the continued and consistent hard work of the staff.
"I am very proud of our pupils and they deserve every praise."
A number of pupils at the school achieved more than 13 grades at A-C.
They included Sara Ellis who received three grades at A* and A, four Bs and seven Cs.
Demi Lewis attained three A*-A grades, two Bs and eight C grades, while Rachel Cooper scored two A* and A grades, six Bs and five Cs.
Twin sisters Georgia and Ellie O'Sullivan also achieved excellent results with Georgia receiving two A* and As, six Bs and five C grades with Ellie achieving one grade at A* A, two Bs and 10 C grades.
St David's High School
St David's High School in Saltney recorded another set of excellent GCSE results.
97 per cent of Year 11 pupils achieved five or more GCSE passes at grades A*-G with 74 per cent of the cohort achieving the Welsh Level 2 Threshold of five
GCSE passes at grades A*–C.
Within this, 57 per cent of pupils achieved five GCSE passes including mathematics and English and 74 per cent of the year group achieved the Level 2 Welsh Baccalaureate Intermediate Diploma
Further down the school, 68 per cent of 4-year-old students in Year 9 achieved a GCSE grade of A* to C in personal and social education.
Headteacher Tony Davidson said: "You don't achieve these sort of results by chance - it's down to effort, determination and commitment.
"Results in English, mathematics and science place us well above the local authority and national average.
"Students of all abilities have approached their GCSE examinations with considerable energy and determination, and teaching staff have provided excellent support and guidance.
"The support of parents has been outstanding," he added.
St Richard Gwyn Catholic High School
CHRISTIAN Jones and Megan Challenger were among the stand out performers at St Richard Gwyn Catholic High School in Flint.
Christian picked up eight A*s and two A grades while Megan celebrated five A*s and four A grade passes.
Headteacher Ronald Keating shared the joy of pupils as they were handed their long awaited grades.
He told the Leader: "In our 60th anniversary year we are delighted with Year 11 success at GCSE.
"This builds on the continuing journey of school improvement at St Richard Gwyn with the celebration of another outstanding year of learning."
More than 70 per cent of the students achieved five A*-C passes at GCSE with 100 per cent achieving A*-G grades, which Mr Keating said demonstrated pupils' dedication and hard work together with that of teachers and staff at the school.
"Parents will be proud of their children's achievements," he said.
"We congratulate all our students staying on to our excellent sixth-form provision here and those going on to further education locally and wish them every success in the future."
Ysgol Maes Garmon
STRAIGHT A pupil Rhiannedd Gwilym was the toast of Ysgol Maes Garmon
Megan Groves achieved two A*s and 10 A grades, while Kiera Thomas collected four A*s, eight As and two B grades.
A record number of pupils at the school in Mold achieved five A*-C grades with more than 20 per cent of all passes achieved at A* or A.
Bronwen Hughes, headteacher, said: "These excellent results are due to the hard work and dedication of students and staff and are a firm foundation for them to move on to the next stage of their education or training.
"I would like to congratulate our students, thank their parents for their support and praise the efforts of the teaching and pastoral staff."
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