Secondary schools have been accused of going to extraordinary lengths to boost the grades of borderline pupils while neglecting the majority.
Henry Maitles, of the University of the West of Scotland, has attacked what he calls a "neo-liberal, league table-type agenda" under which depute heads are literally "driving around, picking up kids to take them to exams to keep schools looking good in league tables".
Their motivation was to improve their league-table scores rather than a desire to benefit individual pupils, he said.
Professor Maitles told delegates at the recent annual conference of the Scottish Educational Research Association: "This A to C (grade) economy means that pupils who are never going to get a C are abandoned, as are those who are likely to get As or Bs, and the focus is on getting those on the cusp of D or C to C.
"Things like citizenship are put on the back-burner and all efforts are put into that tiny group of people."
He told TESS: "If you've got 100 kids and instead of 93 completing you have 97 completing, you go from being a failing school to being a successful school."
His criticism was echoed by Professor Helen Colley, professor of lifelong learning at Manchester Metropolitan University, who compared the league-table agenda to a kind of extreme "medical triage". Those either near death (E grade or below) and those unlikely to die but still needing help for, say, a broken arm, (grades A to C) were abandoned to their fate.
School Leaders Scotland's general secretary, Ken Cunningham, said that while teachers did their very best for individual youngsters, for example by driving them to exams, league tables added a different dimension and drove people to do these things "in order to push up numbers, rather than for any educational merits".