A breakdown in family life has led to schools having to cope with a generation of children with few moral values, a teachers' leader warned yesterday.
Philip Parkin, the general secretary of Voice, the union formerly known as the Professional Association of Teachers, said that parenting skills were declining "as one generation succeeds another".
As a result, children were turning up to school too hungry to learn, having not even seen a parent before their arrival at school. Many had "tribal loyalties" to local gangs rather than their parents, he added.
Some youngsters aged as young as 10 were having to go home to look after a younger sibling until their parents arrived home from work.
"Children come into school hungry who don't actually see a parent before school every morning because they've got themselves up and come into school by themselves," Mr Parkin said.
"Children, also because of time constraints, (possibly from one-parent families) are going home in the evening and letting themselves in and are even having to look after younger siblings until their parents come home."
Some parents were even keeping their children home during the day because they wanted company at home.
"I feel very uncomfortable about the direction in which our society is going," Mr Parkin told his union's annual conference in Daventry. "If successive generations of parents become less skilled at the job then what is learnt becomes increasingly diluted as time goes by."
Mr Parkin singled out "the shortening of the length of many relationships", "the creation of many more step-families" and "the emphasis on going out to work" for reducing the value and worth of the role of the full-time parent. They had "significantly changed the character of childhood".
"If there is no functioning parent there is no food in the house, no one washes your clothes or organises socialising for you, you don't get taken to the GP, dentist or optician," he said. "You live in chaos."
As a result, teachers found pupils in their schools who were "very difficult to deal with". "We may come into contact with children from severely dysfunctional families," he said.
Mr Parkin, a former deputy head of a Grimsby primary school, blamed "adults who try to commercialise children and sell them things that are not beneficial to their wellbeing; adults who promote the cult of celebrity; adults who promote greedy, selfish behaviour" for creating "the social climate in which such behaviour flourished".
Schools were increasingly having to take on the role of parents – and have already been asked by ministers to check for obesity, whether pupils had joined gangs, weapons and under-age drinking. "Why aren't parents being asked to take on these responsibilities?" he asked.
Ministers had focused too much on parents' rights rather than their responsibilities, he said. "Our members have been telling us for quite some time now that schools are being required to take on more and more of the responsibilities that rightly belong to parents: and to provide more of the stability in children's lives which should be provided by families."
The union went on to pass a motion backing a drive to set up armed services cadet forces in state schools to help improve discipline. The plan is supported by the Government.