A third of teachers are forced to deal with physical violence from pupils, including one girl telling her teacher she would "kick the smile off her face", a survey reveals.
Poor parenting could be fuelling bad behaviour in schools, the report suggests, as bad behaviour reaches a peak, with pupils kicking, punching, pushing and shoving school staff, according to a poll by the Association of Teachers and Lecturers (ATL).
ATL general secretary Dr Mary Bousted said there is a minority of children who have a "total disregard of school rules".
These youngsters are just as likely to be "over-indulged" middle-class children as those from poorer homes, she said.
ATL's annual behaviour survey found that a third (33.1%) of those questioned said they have had to deal with a violent pupil in this academic year.
Of these, a quarter (28.3%) said violence had been aimed at them and a quarter (28.7%) said it had been towards a teacher.
And 80.6% said that they had dealt with violence aimed at another pupil.
The vast majority (88.7%) said they had been faced with pushing and shoving, with three quarters (74.8%) saying they had dealt with punching and hitting.
Other types of violence included kicking (56.7%), spitting (18.5%), biting (16.4%) and scratching (16.4%) while 4.2% said they had dealt with pupils stabbing or attempting to stab someone.
One member of the support staff at a secondary school in Wales said: "I had a female student threaten to kick the smile off my face, in front of a whole class."
And a teacher at an English state secondary told researchers: "Six boys were refusing to work, throwing glue, pens, fighting and throwing books."
The survey, which questioned 814 people working in UK schools, found that the vast majority of bad behaviour was low level disruption, such as pupils talking in class and not paying attention (cited by 87.1%) followed by students being disrespectful, by refusing to comply with rules, ignoring requests and using mobile phones during lessons (84.7%).
The poll suggests that poor parenting and problems at home are contributing to naughty behaviour in schools.
Almost three quarters (72.9%) blamed a lack of positive role models at home, while more than two fifths (42.5%) cited neglect at home as a factor.
Nearly two thirds (62.7%) said that breakdown of relationships within a family was a main cause, and 72.8% said pupils behaved badly because they were seeking attention from their classmates.
Poor emotional health, breakdown of friendships, puberty, poverty, a lack of interest or struggling to understand lessons and pupils unable to see the value of education were also among the reasons given.
A special educational needs staff member at a secondary school in England said: "Pupils are often confused, lack stable families, lack discipline or discipline is inconsistently applied."
And Victoria Malcolm, an English primary state school teacher said: "Pupils know that there is little school staff can do to enforce discipline. They are not 'afraid' for want of a different word.
"Behaviour folders, traffic light charts, even talking to parents does nothing to encourage certain children to improve their behaviour."
The poll, which questioned 814 teachers, lecturers and support staff, found that 76.9% said their school favours detention to deal with unruly pupils, while 75.8% said suspension, 74.7% said warnings are used, and 73.6% said parents are called or summoned.
But some teachers said they feel they are not supported by parents.
A member of a management team at an English state primary school in England said: "A change in pupils' behaviour is not helped by the lack of respect that parents show towards staff in school - there is no wonder that some pupils are rude when this is what they see as a role model."
Bousted said: "A minority of children are very aware of their rights, have a total disregard of school rules and are rather less aware of their responsibility for their own learning and how to show respect to staff and other students. This can apply as much to over-indulged middle class children as those from challenging families.
"It is not surprising to see that poor behaviour is often attributed to problems at home. Teachers need to work with parents to encourage good behaviour and parents should be acting as good role models by supporting staff and helping them create a more positive learning environment for their children."
Suggested For You
Get top stories and blog posts emailed to me each day. Newsletters may offer personalized content or advertisements. Learn more