England’s exam regulator said it was forced to mark down thousands of results owing to “implausibly high” predictions submitted by teachers.
Schools assessed grades for pupils after exams were scrapped amid the coronavirus pandemic.
A-level results day descended in chaos as 39.1% of teachers’ estimates were adjusted down by one grade or more through an algorithm.
According to regulator Ofqual’s analysis, pupils and schools in disadvantaged areas were marked down the most harshly by the statistical model used to replace exams.
Furious pupils today protested outside Downing Street and called for the Education Secretary to be fired.
Placard-waving demonstrators chanted “Sack Gavin Williamson!” and “Teachers not Tories!”
Harry Mayes, from Stoke Newington in north London, missed out on a place at his favoured university after receiving A, B and C grades.
The 18-year-old, who hoped to study neuroscience at Bristol University and had grades of A*, A and B submitted by his teachers, called the system a “complete injustice”.
“I’m a free school meals student and it seems like people like me have been lowered the most,” he said.
A 19-year-old student, from Streatham, South London, was predicted one A* and three As in sciences and maths and hoped to study medicine at Imperial College London.
But he was “shocked” to have received an A, two Bs and a C.
The teenager, who declined to be named, said: “I didn’t see it coming. Being based on your school, rather than the individual’s performance, is quite dehumanising, isn’t it?
“Medicine in itself is really difficult to get into, you have to do entrance exams and interviews, so I had to struggle through all of that just to be told an algorithm would decide my grades.
“It feels like all of my work this year has been made redundant.”
Labour’s deputy leader Angela Rayner accused the Government of making an “absolute mess” of exams grading.
She said: “We believe the only option that the Government have got now is to go back to the teacher-awarded grades because they’ve made such a fiasco.
“A lot of children who have worked incredibly hard have been devastated by a system that’s been completely flawed and has taken into account the school’s previous history rather than what that child’s been able to achieve this year.
“I think that’s devastating and there’s baked inequality in what’s happened.”
Commons Education Committee chairman, Conservative MP Robert Halfon,called on the regulator to publish details of the algorithm used to make its calculations.
“Some figures suggest that disadvantaged students have been penalised again,” he said.
“I am also worried about further education colleges because they have been improving in recent years and yet they seem also to have suffered under this grading system.
“If the model has penalised disadvantaged groups this is very serious and if it has disadvantaged colleges that has to be looked at.
“Ofqual will have to adjust the grades.”
Liberal Democrat education spokeswoman Layla Moran said the “shambolic handling of A-level results has left many young people in crisis”.
She added: “Gavin Williamson is an Education Secretary out of his depth and out of excuses.
“He must take responsibility for his mistakes and step down with immediate effect.”
Curtis Parfitt-Ford, 18, who went to Elthorne Park High School, West London, threatened Ofqual and the Government with legal action unless the system is changed.
He has started a Change.org petition calling for: “no ‘marking down’ of individual pupils based purely on them having gone to a less good school; a free appeals system open to any pupil; more weight given to our own teachers’ assessments, as they are better placed than an algorithm to judge us as individuals.”
More than 116,000 people have signed the plea.
Curtis, who got the grades he needed to study computer science at Southampton University, said: “For a lot of pupils, the algorithm doesn’t even consider what our own teachers predicted we’d get. There isn’t a proper appeals process.
“Worst of all, pupils from poorer schools, with lower results historically, are due to get automatically marked down by the software.”
Prime Minister Boris Johnson has insisted that he has confidence in Mr Williamson and described the system as “robust”.
Ofqual said it was “working urgently” to set out how mock exam results will form the basis of an appeal, but further details will not be ready until next week.