Being bullied may be seen as one of the big scourges of schooldays but 71% of pupils admit they have been the bullies picking on others, a survey suggests.
Bullying can take many forms
In a survey of 3,000 secondary school pupils, 71.4% admitted to having been the perpetrator of a bullying incident.
Charity Beatbullying, which carried out the survey, says it gives an insight into the scope of the bullying problem.
Teachers' leaders said they were not surprised by the figures, but believe schools handle the issue effectively.
In the survey, carried out between 2005 and 2007, children were asked if they had ever bullied and, if so, what had led them to do it.
Reasons given for being a bully included a fear that if they did not do it first it would happen to them; because their friends did it; or anger at another individual. A small number of children - 2% of those surveyed - did it because they thought it made them popular.
For the purposes of the survey, bullying was defined as "being bullied twice a week over a period of six months and involving more than two types of bullying".
Beatbullying chief executive Emma-Jane Cross said: "These figures show that the majority of bullying taking place in schools is not perpetrated by a recitative minority.
"Most bullying is low-level, perpetrated by young people who are easily led or incorrectly believe that it is inevitable, or worse still, that it makes them popular.
"The good news is that these young people are within our grasp, they are not the hard to reach with severe behavioural problems.
"Beatbullying can continue to educate these young people to easily change their behaviour."
General secretary of the National Association of Head Teachers Mick Brookes said he was "not surprised" at the number of children admitting to bullying and believed it showed their honesty.
He believes dealing with bullying is part of growing up and associated with learning about what is acceptable and unacceptable behaviour.
He said controls on behaviour need to be imposed on children, but once those controls are taken on board - particularly in relation to bullying - they can be removed because you rely on children to be self-disciplined.
He admitted that what constitutes bullying can get confused.
When children report an incident as "bullying", teachers have to make a careful assessment of whether there is a genuine case or it is something more innocent, for example, one child accidentally knocking into another child in the playground, he added.
But he admits that in some areas there has been an increase in bullying incidents, especially where there has been a "breakdown in standards of behaviour" in the community, which are then brought into school.
But overall he believes schools are dealing with bullying effectively.
He said: "I applaud what schools are doing. They are paragons of virtue in what can be very rough environments."
Beatbullying is pro-active in tackling and preventing bullying and runs a peer mentoring scheme to help both bullies and those on the receiving end.
A spokesman for the Department for Children, Schools and Families said bullying was totally unacceptable and that it used peer mentoring schemes to tackle it.
"Peer mentoring ensures than older, well respected pupils help teachers to stop bullying early and act as role models to younger pupils. This approach has been proved to be successful time and again."