Labour: 'Too much structural reform damaging learning'
The number of under-performing state secondary schools has more than doubled in a year.
New leagues tables show 330 failed to reach 40% of pupils attaining five good GCSEs including Maths and English.
Ministers have toughened exams and banned re-sits and some vocational qualifications from the tables.
Labour's Shadow Education Secretary, Tristram Hunt, says teachers and pupils are suffering because of government interference.
He said: "Too much chop and change, too much chaos, too much structural reform is getting in the way of learning."