A civilised society should be judged on how it takes care of its most vulnerable and disadvantaged citizens. Sadly, our record in looking after one of the most vulnerable groups, children in care, is not good.

First some basic facts. There are about 60,000 children in public care in the UK on any given day. The annual cost of looking after them is pound;2.4 billion. Some 42,000 of these children are placed with foster carers; 8,000 are living in children’s homes and residential special schools, with a further 7,000 placed with relatives.

The Fostering Network estimates that there is a shortage of at least 10,000 foster families. The total annual cost of a child in foster care is about pound;20,000, with some independent fostering agencies charging up to Pounds 50,000 per child. The annual cost of residential care in children’s homes is, on average, pound;100,000 per child. Despite this huge investment of resources, the outcomes are distressingly inadequate.

Let us look at some disturbing data published by the Department for Education and Skills:

* Only 9 per cent of children in care for a year or more achieve five A*-C grade GCSEs compared with 54 per cent of all children.

* According to one study, a third of people sleeping rough had been in care when they were children.

* The proportion of children continuously looked after for at least 12 months aged 11 who achieve level 4 in key stage2 English and maths is only half of that for all children.

* 9 per cent of looked-after children aged 10 or over are cautioned or convicted for an offence each year - three times the rate for all children of this age. Sadly, far too many will become young offenders who will be in and out of prison for most of their lives. Indeed, one study showed that a quarter of all adults in prison had been in care for at least part of their childhood.

* At age 16, 55 per cent of looked-after children remain in full-time education or training, compared with 75 per cent for all children aged 16.

Children in care frequently change both their home and their school.

Shockingly, 13 per cent of children in care experience three or more placements a year, often with adverse impacts in terms of their emotional and behavioural difficulties. How can any child flourish when they move home three times a year?

A recent report by the Social Exclusion Unit said there were four other key reasons why children in care underachieve:

* Young people in care spend too much time out of school.

* Children do not have sufficient help with their education if they get behind.

* Carers are not trained to provide sufficient support and encouragement at home for learning and development.

* Children in care need more help with their emotional, mental or physical health and well-being.

So what is the solution to the problem? A key to improving provision for vulnerable children must be to provide greater stability. Let us hope that the setting up of children’s trusts by local government will produce a more integrated approach.

We need to ensure that schools and local authority children’s services work more closely together. Improvements are also being made in the adoption procedures. Local networks of specialist schools could also provide support. Some specialist schools now use minibuses to bring children in care to school, and this at least helps to prevent these children from having to change schools when they change foster parents.

But much more needs to be done. We must have better data and more research.

Why are children in care moved so frequently? More importantly, we could place more children in care in suitable boarding schools. At present , we have 34 state boarding schools with some 4,000 boarders. The average boarding charge is pound;7,000 per year - much less than the cost of a foster family and dramatically less than the cost of residential care, although suitable arrangements would also need to be made for school holidays.

Charities, such as the Royal Wanstead Children’s Foundation and Christ’s Hospital arrange for thousands of vulnerable children to attend independent boarding schools. The Specialist Schools and Academies Trust, which now has 2,600 British schools affiliated to it, strongly supports an increase in state-supported boarding provision for children in care.

We hope that some of the new academies will have boarding provision. Many specialist schools have indicated a willingness to set up boarding units.

It costs about pound;30,000 per bedroom to build a dormitory, or pound;3 million for 100 beds. Even with the annual recurrent costs of pound;7,000 per year per child, the cost of boarding places would be much less than for a council to run a children’s home.

The DfES is considering a number of pilot schemes to test the feasibility of expanding boarding for children in care. This is a welcome step, but we need to do more, including:

* Compare the relative cost of providing council-organised children’s homes or residential care accommodation with costs in either state or independent boarding schools.

* Determine how many boarding-school places could be provided in maintained schools by building boarding units on to existing day schools, and at what capital cost, and what annual maintenance cost.

* Agree on the criteria for choosing vulnerable children to be placed into boarding schools. Clearly, vulnerable children should be placed in boarding schools only with the consent of both the child and the school.

Sir Cyril Taylor GBE is chairman of the Specialist Schools and Academies Trust