Aggression between conspecifics in a group typically involves access to resources and breeding opportunities. One of its most common functions is to establish a dominance hierarchy . This occurs in many species by aggressive encounters between contending males when they are first together in a common environment.  Usually the more aggressive animals become the more dominant.   In test situations, most of the conspecific aggression ceases about 24 hours after the group of animals is brought together.   Aggression has been defined from this viewpoint as "behavior which is intended to increase the social dominance of the organism relative to the dominance position of other organisms".  Losing confrontations may be called social defeat , and winning or losing is associated with a range of practical and psychological consequences. 
Teach students conflict-resolution skills. Children might resort to aggression because they lack the words or skills to solve problems non-physically. Help them learn to resolve conflicts without acting aggressively by teaching them the basics of talking things out: staying calm; allowing each person to have his or her say without being interrupted, blamed or put-down; using "I messages" to convey feelings; and considering another's point of view. Designate an area of your classroom as a "peace corner," a place where students can go to settle conflicts and decide on a resolution. After they have spent time in the peace corner, students should inform you of their decisions.