Using census data for Argentine prisons for the period 2002-2005, this paper presents evidence of the positive effect that prisoner education programs (primary and some part of secondary schooling) have on in prison conflictive measured as sanctions or violent behavior of the prisoner. In order to over-come the problems of endogeneity that education decisions generate we use an instrumental variables approach. Our results show a decrease in participation in violent conflicts and bad behavior which can be partially attributed to education.