Students seem to be aware of bullying’s impropriety. Surveys of Midwestern students in the mid-90s found that 43 percent of students said they would try to help the victim of a bully, 33 percent felt they should help, even though they didn’t, and only 24 percent felt bullying was none of their business. However, there is some ambiguity in their feelings on the subject. A majority of those surveyed felt that victims were at least partially responsible for bringing the bullying on themselves and that bullying toughened a weak person. Some even expressed the view that bullying taught victims appropriate behavior. 
It is quite illogical, of course, to believe that a behavior can be both wrong and deserved. That paradox is readily resolved by an appeal to self-interest. If you endorse the use of such tactics against someone else, you are left with no argument against their application to you. It is not a coincidence that virtually every ethical system, religious or secular, contains some variation of the Golden Rule.
If you observe someone being victimized by a bully, self-interest dictates that you intercede on behalf of the victim, if that can be done safely, or that you walk away and enlist the help of an adult in authority.
That raises the issue of whether it is right to “snitch” on a classmate, even one you know is doing wrong. The answer, stated bluntly, is that you are in school, not the mafia. It is no reflection on your honor to try to help someone who is being hurt, physically or psychologically. Indeed, it is dishonorable not to do so. Mature people report harmful behavior to the proper authorities, if discretion prohibits them from intervening directly.
Your own safety in making such a report is a consideration, of course. Report bullying to an adult you trust to keep the source of the report confidential. You’re trying to be a good citizen, not a hero.
There is a secondary benefit to be derived from reporting bullying to school authorities: adults commonly underestimate how much of it occurs. The more bullying is brought to their attention, the stronger the motivation for establishment of effective policies to reduce it.
A second way to reduce bullying is to be inclusive of classmates who could easily be left out. Physical size is less a factor in the targeting by bullies than the perception that the potential victim has few or no close friends.
Since discretion is ever the better part of valor in dealing with bullies, it is fair to ask why students who are not bullies or victims shouldn’t just stay out of the matter altogether, rather than working toward elimination of bullying from schools. The general answer is that bullying poisons the school experience for everyone—and possibly life beyond graduation, as well.