Violent behaviour among school students and its predictors were investigated. Selected children (2170) were requested to complete a self-administered questionnaire. Initiating violent assaults in the 18 months prior to the study was reported by 51.0% of boys and 20.9% of girls. Multivariate logistic regression analysis pointed to 16 predictive variables for violent behaviour; few were related to family background whereas the majority were related to the children themselves. Violent assaults were more likely to be initiated by boys and those who were dangerously daring and risk-takers, often fought verbally, threatened to attack others, were cruel to animals, disrupted class discipline, were truant from school or ran away from home and were disciplined by corporal punishment by their parents and their teachers. School-based prevention and intervention programmes addressing modifiable predictors should be considered.