Former education secretary Estelle Morris has questioned whether the government really knows what it is doing with its school reforms.
Estelle Morris resigned as education secretary in 2002
The ex-Labour Cabinet minister said in a lecture there was "a risk we thrash around from one initiative to another" without asking essential questions.
Speaking in London, she warned that the gap between the highest and lowest achievers had barely changed.
Key questions needed answering, she said, before more reforms are begun.
Baroness Morris of Yardley, who spent five years in government - first as schools minister and then as education secretary - said ministers should be asking themselves why other countries were doing better.
At the second annual lecture of the National Education Trust, she said the limited impact policies had made on the achievements of disadvantaged children was a cause for concern for politicians and educationalists.
Ministers should be asking whether their relationship with educationalists was as it should be, she said - and whether the right "levers" for improvement were being used.
The influence of the league tables and national tests on schools has long been criticised by the teaching unions.
Many argue that they lead teachers to concentrate on too narrow a curriculum and to "teach to the test".
And a number of reports have suggested that political interference in schools has hampered children's progress and prevented teachers from being creative in the classroom.
England has also slipped down an international league table of educational achievement compiled by the Organisation for Economic Co-operation and Development.
A spokeswoman for the Department for Children, Schools and Families said the vast majority of children went to better schools, enjoyed better health and lived in better housing and in more affluent households than they had 10 years ago.
"We are closing the attainment gap and standards are rising across the board - in the last 10 years over 100,000 more pupils have achieved five good GCSEs and in the past four years the attainment gap between children on free school meals and those who aren’t has narrowed by four percentage points at Key Stage 2 for English," she said.
“But we know challenges remain which is why we published our 10 year Children's Plan and are targeting the lowest achieving children with a revamped secondary curriculum, quality qualifications and apprenticeships and investing £1bn in one-to-one tuition and catch up classes.
"It is a top priority for us to reduce inequalities between the poorest performers and the rest. We are determined to make sure that all children can reach their full potential, whatever their background, gender or ability."