Children of five years old are starting school still wearing nappies, according to a shocking new report.
Some children have been so poorly parented they are unable to speak or even recognise their own name.
The Centre for Social Justice (CSJ), a centre right think tank founded by Iain Duncan Smith, called the evidence it had compiled between 2007 and 2012 'heart-breaking', and said some children had such terrible early home lives that they were condemned to be at a disadvantage for the rest of their lives.
The study also revealed that many hundreds of thousands of teenagers leave school every year without achieving adequate GCSEs, and that boys from poor, white backgrounds were falling further behind their classmates than any other identified group.
"The early years experiences endured by these children have been so abysmal that they begin compulsory schooling absolutely not ready for learning and, potentially, permanently disadvantaged," a CSJ spokesperson said.
One headteacher told the think tank: "In the last three years we have had to toilet train children who came to school in nappies at age five. Parents ask me how we managed to do it. Many of them just can't be bothered, they think it's our responsibility to do it for them."
Another said that it was very common for youngsters to start school unable to cope, with three-year-olds who "commonly act like 12 to 18-month-olds".
"'They don't even have the concentration to talk and say an answer in any kind of sentence," she said.
"We've had children that don't answer to their name. They don't recognise their name...they're not toilet trained."
Sir Robin Bosher, chairman of the group that drew up the report, said that one in ten children he observed was "so unsociable that they hurt others, adults and other young children".
Statistics cited by the report showed that one in eight five-year-olds cannot write their own name or other words from memory, while 6 per cent of boys of this age group did not know that print is read from left to right and top to bottom.
Research undertaken at Kent Community Health NHS Trust in 18 primary schools found 24 children did not know how to use the toilet and still wore nappies, with one school having to replace two classroom carpets after 'accidents'.
Frustrated teachers complained they are having to waste valuable lesson time sorting out children who have no awareness of their need to visit the lavatory, something a teaching union said came down to a 'lack of parenting skills' at home.
In a programme being launched in nurseries in the Dover and Deal area of the county, school nurses and health visitors will give advice and support to help get children out of nappies.
The scheme is likely to eventually be rolled out across the UK.
Speaking to the Mail, one school nurse, Chris Beer, said teachers were 'concerned' that they were spending 'less time teaching and more time helping children who were having accidents'.
"What we hope is that by working with children who are struggling in nursery we can support them so by the time they get to school they will be clean and dry and can concentrate on learning."
The Association of Teachers and Lecturers said that despite toilet training being parents' responsibility because 'children are in school it's then left to teachers to deal with the situation'.
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