Thousands of children are struggling at school because of family breakdown and bad parenthood, teachers said yesterday.
They often arrive at school unfit for lessons after being allowed to drink alcohol, stay out with friends and use social networking websites late into the night, the Association of Teachers and Lecturers claimed.
Mary Bousted, the union's general secretary, said: "Children's mental health is becoming a real issue.
"A lot of that is because they are coming from homes which are severely disrupted because of family breakdown or parents not providing the boundaries needed for young people.
"Too often they are coming to school completely exhausted and unable to concentrate. Too many parents just seem unable to fulfil their responsibilities to young people."
At the union's conference in Torquay on Monday, members will urge the Government to recognise the extent to which "social dysfunction and family breakdown" are undermining children's grades.
Dr Bousted said the decline of children's home life was one of the biggest problems facing education.
"Now children can go out every night and they believe it is their right to do what they want when they want to do it. You have Facebook, internet chat rooms, children have computers and televisions in their rooms - they are distracted at every corner.
"Parents are not firm enough and too many fail to properly prepare their children for school. The long-term consequence is that children will not appreciate the importance of school and, as a nation, we will not get the results we want."
