Three of the borough's worst-performing schools face potential closure unless they can improve results by 2006.
The Government's Education Bill, confirmed in legislation on Friday, sets the minimum target of 25 per cent five A* to C grades at GCSE.
Ravenscroft School in Barnet, The Edgware School in Edgware and Whitefield in Cricklewood all scored below that threshold in league tables published last week, way below the borough's 55.8 per cent average.
Nationally, 373 schools fell short of that target this year.
Dr Alan Davison, headteacher of Mill Hill High School, said the league tables in their current format were "history".
He pointed to this year's value-added league tables which track improvements in individual pupils piloted for 200 schools, including Whitefield as the way forward.
In these figures, the Claremont Road school scored 99 per cent, just below the average of 100 but respectable improvement.
Dr Davison, chairman of Barnet Headteachers' Conference, said: "Any school that doesn't do the best for its pupils should be closed but not based on raw data from league tables.
"I'm certain these three schools are not doing any worse for their students that anyone else. Setting a target of 25 per cent is a nonsense."
A spokesman for the Department for Education and Skills said: "There are a lot of measures being targeted at schools achieving below these targets. Exam performance is not the only criteria for assessing a school."
Councillor Alison Moore, Barnet Council's cabinet member for schools, remained philosophical this week.
"We will be robust in supporting and challenging those schools to meet that standard," she said.
"We're talking five years' time and if we look at the cycle of schools, for example Whitefield which we have put a great deal of effort into it has made an enormous jump this year and we would expect by 2006 for that school to be out of that category."
The North London Collegiate School in Canons Drive, Edgware, was among the best independent schools in the country.
Students at the all-girls school recorded 97 per cent five A* to C grades.
Dame Alice Owen's School in Dugdale Hill Lane, Potters Bar, scored 90 per cent A* to C grades, making it one of Hertfordshire's top schools.
November 28, 2001 19:28
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