A chronic shortage of foster parents means that some children in care are being forced to move up to three times a year, research has shown.
An extra 10,000 foster carers are needed to plug gaps in the service, campaigners say.
A survey by the Fostering Network found that 13 per cent of looked-after children had moved to three different temporary families every year.
The constant moves are having a devastating impact on the education of the most vulnerable children.
Almost half of foster children have moved school at least once while under the care of a local authority and one in five have moved at twice or more.
Vicky Swaine of the Fostering Network said: "One 16-year-old boy we talked to had been moved 17 times during his schooling. There is not just the emotional upheaval of moving families but also the damage that changing schools does to their educational prospects.
"Some foster carers are driving children up to 60 miles just so they can stay in the same school."
She added: "These are some of the most vulnerable children in our society and they need real stability but the shortage of carers means they have to be moved from pillar to post.
"The shortfall also means that children end up miles from their birth families so contact becomes difficult."
About 50,000 children are living with 37,000 foster families in the UK. Two thirds of children under local authority care are now with foster families rather than in homes.
Looked-after children have the worst educational attainment in Britain. Only 11 per cent achieved five GCSEs in 2005, compared with 56 per cent of all children, and less than 5 per cent go to university.
The Fostering Network is calling on the Government to invest an extra £750m in the service to recruit, train and retain more carers.
It wants to see a national system of allowances paid to foster parents. "Some local authorities do pay, but around half of carers do not get anything at all, even though some councils also demand that you give up work to care for certain children," Ms Swaine said.
"That policy, in effect, says that the Government expects you to be part of the social care profession but that you shouldn't get any kind of payment for it. We would like to see the role of a foster carer being seen as a career within itself."
The network said that coverage of the selection process for carers had led to many people believing - wrongly - that they would not be considered because they were overweight or single, among other factors.Reuse content