SAFE sex is often rejected by young men who want to be seen as hard-driving studs rather than caring, responsive lovers, a new book claims.
It says that some lads use sexual harassment - groping, teasing and graffiti - to gain power over girls and other, sidelined boys.
Many boys go to great lengths to prove to classmates that they are not "soft" or "sissyish".
One high achiever, who went on to gain a first-class degree from Cambridge and to undertake a PhD, took books up a tree in order to avoid homophobic bullying at his public school, according to the book, Failing Boys, edited by academics at London's Institute of Education.
Former English teacher David Jackson says that peer group pressure, particularly over school sport and over sex, needed to be exposed.
"Preventative work with boys makes cost-effective sense when you consider how much of our current time, energies and resources already go into picking up the broken pieces after boys' routine acts of vandalism, violence, stealing, display and disruption."
Mr Jackson said behavioural management techniques, such as homework monitoring, were useful but had to work hand-in-hand with an understanding of boys' traditional, macho culture.