I agree with most of the posts here re. the 0-Tolerance issues. I do, however, take a little different tactic as to how to deal with them.
As an example- I have had more than one student over the years approach me with a bully problem in school. They do not want to get into trouble at school and weren't sure what to do. So I start talking statistics.
Most assaults are committed by someone known to the victim. In the case of a bully- the attack is not just about the violence, it is usually about humiliation as well. A bully will "warn" his intended victim more often than not. The point is, that the attack is not, usually, a "surprise". The victim usually knows that it is coming.
That being the case, I encourage them to immediately go to 1- their parents, and 2- teachers and administrators with this information. If the parent is not sure what to do or unwilling to do anything ( I can't believe when that happens), the next step for either parent or student is to go to administrators and demand that the meeting be put on the record, and bring their own recording devices and, if needed, a legal representative. Once the meeting begins- the student or parent outlines what the problem is and who the problem is with- then asks the simple question, "my safety is in jeopardy, what are you, the responsible adult, going to do about this." If or when the administrator refuses to do anything, the student and/or his parent responds by saying that the administration has been warned of this issue, the threat still exists, and if the student fears for his safety or is actually assaulted, he will defend himself appropriately and there will be no reprisals against him. If the administrator says otherwise or falls back on the 0-tolerance policy, then all records of said meeting will be handed over to local media, the school board, and any city/county/state agencies that govern both the school and child safety.
Some of my students have done just this with great success. If the Administrators are going to be lazy or cowardly, why not manipulate them for ourselves?