A "Bully" computer game sends out the wrong signals and should be withdrawn from sale, say UK teachers.
Campaigners claim the game glorifies bullying
They are part of a global coalition concerned about the impact of the game, which has been released in new formats.
Bully: Scholarship Edition "trivialises and glorifies bullying in school", say opponents from eight international teacher groups.
UK retailers say they will not act as censors and will continue to sell the game to children over the age of 15.
The National Union of Teachers (NUT) and the Scottish Secondary Teachers' Association (SSTA) are part of an international group which thinks the game could encourage bullying.
Although it carries a British Board of Film Classification (BBFC) 15 rating, campaigners fear Bully could get into the hands of much younger children.
The game, designed by US-based Rockstar Games and which goes on sale in the UK on 7 March, was originally launched in 2006 but has been updated for the new generation of games consoles - Xbox 360 and Wii.
It features a teenager who adjusts to life at a new boarding school by harassing others, including teachers.
The abuse includes dunking pupils' heads in toilets, photographing them naked and physically assaulting them.
NUT general secretary Steve Sinnott said: "At a time when there is a growing concern about bullying in schools and the increasing violence shown towards teachers, the idea of a game that rewards bullies and those who engage in brutal and savage attacks is irresponsible in the extreme.
"I call upon Amazon, Game, Play and HMV to withdraw this product from sale immediately."
The Australian Education Union's federal president Angelo Gavrielatos said: "We were disappointed when the game was first released in 2006 and we are appalled this new version is said to be more realistic, featuring new methods to torment and bully".
The coalition of countries calling for the game to be withdrawn from shelves includes Canada, South Korea and nations of the Caribbean.
"What a distasteful example to show young people. The game undermines all our work for civility, social engagement and peaceful resolution," said Caribbean Union of Teachers president Adolph Cameron.
HMV told the BBC News website they would not actively promote the game by placing adverts in national newspapers and that their approach would be more discreet, but they would not remove it from sale.
A spokesman said: "As a retailer, we do not censor content that has been cleared by the BBFC.
"We do, however recognise the importance of merchandising such games' titles responsibly and we seek to do this in a manner that is sensitive to both its content and BBFC rating."
The Game group also refuses to withdraw the product from its high street and online stores.
A spokeswoman said: "In the UK, the BBFC and PEGI (Pan European Game Information) are responsible for deciding what video games can go on sale, and every game is given an age rating to reflect its content.
"This title carries a BBFC-15 rating, and we have extensive procedures in place to ensure age restricted games are only sold to customers who are the required age."
The Beatbullying charity group believes the game is sending out the wrong signals to young people.
A spokesman said: "We should not be sending young people the message that violence is the way to resolve bullying.
"Beatbullying seeks to educate young people that bullying is neither cool nor acceptable, and a video game like this, which encourages, glorifies and rewards child on child violence, does nothing but undermine all our hard work.
"With the release of Bully on the Nintendo Wii, young people will physically act out the violence they want to inflict on a classmate and that is frightening."