The current paper applies action systems theory to the phenomenon of school violence perpetrated by children. This framework has been recently applied to understanding other forms of criminal behaviour and was hypothesised to be appropriate for understanding the function of aggression and interaction in school homicides. The data for the study consisted of 93 school-associated violent deaths occurring in North America between 1992 and 1999. Content analysis of these cases produced a set of 29 variables relating to perpetrator actions. In order to test the action systems hypotheses, a Smallest Space Analysis (SSA) was performed. The plot was partitioned according to an angular facet reflecting four modes of interaction, in the spatial order predicted by the model. Additionally, a radial facet was found that was interpreted as reflecting the offender's attempts to attain or preserve their sense of power. These results have implications both for understanding the motives and functions of violent behaviour in schools, as well as offering suggestions for interventions targeted at modifying this behaviour.