One of Victoria's 'top' private schools has been accused by a whistleblower of "systematic cheating" after it granted students an extra year to complete the high stakes International Baccalaureate, an alternative to the VCE.
The schools regulator, the Victorian Registration and Qualifications Authority, investigated Carey Baptist Grammar School in March after a whistleblower raised concerns about the school's conduct
It was alleged that Carey students were given an unfair advantage over those undertaking the IB and VCE at other schools.
In a letter to the watchdog the whistleblower said: "I am writing to inform you of systematic cheating by an independent Victorian school ... Carey Baptist Grammar School has been allowing its students to complete the IB diploma program over three years."
The International Baccalaureate Organisation, the body overseeing the delivery of the program, has also investigated Carey Grammar.
The Kew private school has allegedly been letting students complete the IB diploma program over three years, instead of the mandated two years.
Until recently, the school spruiked on its website that students could accelerate IB subjects, by starting them in Year 10 as part of an "anticipation" program.
In a letter obtained by The Age, Kevin House, the IBO's head of school services in the Asia Pacific, said he had asked Carey to stop advertising its "extended form" of the IB diploma.
He said that if Carey students were on the "adjusted program" the practice must be "phased out at the earliest opportunity".
Mr House said the school needed to adhere to the organisation's "practice of concurrency", which means that the IB diploma is completed over two years.
"I can guarantee we will be following up with the school to ensure that they are being true to their word and that no practices sit outside the spirit of the IB diploma program," he said in the letter.
Carey principal Philip Grutzner was reluctant to respond to the allegations, other than to say that the school had fulfilled all regulations, instructions and audits.
VRQA director Lynn Glover said in a letter to the whistleblower in May that she was concerned about the allegations and had spoken to the IBO.
She said an analysis of Carey students' results by the IBO did not reveal that they had an unfair advantage over students at other schools who completed the diploma program over two years.
The school achieves impressive IB results. In 2015, its students received an average IB score of 36, which equates to an ATAR of 94.4.
The worldwide IB average is 29.9, which is equivalent to an ATAR of 83.85.
In a separate letter, which was written last month, Ms Glover said "corrective measures" taken by the IBO would address the issues raised by the whistleblower.
But the whistleblower said that Carey students had been given an unfair advantage and the conversion of their IB score to ATARs was "unwarranted".
They said this disadvantaged hardworking VCE and IB students who worked within established rules.
"Not everyone can be a doctor or a lawyer but it's really important that they have an opportunity," they said. "This is not equal footing."
Ms Glover told The Age that IBO, which is the owner of the IB qualification, would ensure that Carey met its requirements.
The IBO said starting some IB courses in year 10 "was minimally condoned ... in the past".
But it said this practice had "now stopped being supported by the IB".
"As such the IB has advised that Carey Baptist should now discontinue this practice."
Schools have also been accused of bending the rules to give students more time to complete their VCE subjects. In May, two Haileybury teachers who were sacked from the school's Chinese campus alleged they were ordered not to tell a Victorian Curriculum and Assessment Authority auditor that VCE classes were being taught in Tianjin over three semesters instead of two.