Government guidance sent to headteachers last term includes case studies of several secondaries that focus on youngsters believed to be at risk of narrowly missing C grades in the exams.
But the guidance has been attacked by teachers' and parents' leaders.
Robert Coe, a director of Durham University's curriculum, evaluation and management centre, said: "The whole idea of targeting particular pupils is deeply immoral. It makes some seem more important than others. (Although) I welcome this guidance, if it means the Government is now being more honest about what is going on in schools."
St George's Church of England secondary, in Gravesend, Kent, featured in the guidance said it had identified 63 pupils capable of improving from DE to grade C. Teachers monitored each of these pupils' progress and alerted senior staff if any were not performing well. Warley high, in Sandwell, west Midlands, targeted those "who are predicted to gain a grade D in a particular subject, but, with extra support, could achieve a grade C or better".
These students were mentored by senior staff. Another of the five featured schools said it had directed one-to-one mentoring at 92 targeted GCSE pupils.
George Salter high, in West Bromwich, said it had transferred a group of pupils from a design and technology course to photography after it emerged they were unlikely to gain a GCSE in DT.
Margaret Morrissey, of the National Confederation of Parent-Teacher Associations, said: "It's really important that schools don't focus on one group of children at the expense of others."
Mick Green, acting head of George Salter high, said: "I would be hypocrite to say I was happy with the idea of targeting 92 pupils. Schools should target every pupil, shouldn't we? But when I started at the school a year ago, we were facing a score of 10 per cent five A*-Cs and the prospect of being closed down. In the end, we got 24 per cent. All our pupils can now get study support and extra revision classes."
Both St George's and Warley schools denied targeting certain pupils at the expense of others. Both said that independent reports had praised their support for non-borderline students. John Martin, executive head at Warley, said: "We provide maximum support for all our youngsters."
The guidance, Seeking alternatives to GCSE study leave: some case studies aims to encourage schools to consider alternatives to sending pupils home for revision before exams. Tactics cited include after-school, Saturday and Easter revision classes and giving lessons in a subject just before pupils take its GCSE.
Another school, John Hunt of Everest in Basingstoke, Hampshire, offers pupils the chance to win pound;100 if they improve their attendance and "study habits".
A DFES spokeswoman said: "The guidance provides case studies from five schools, each of which used a wide range of strategies, sessions for borderline students being just one."
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