I designed a RBSD-type program, Reality-Based Zero Tolerance, to better train schools with these issues. It is based on the principle that to be a good teacher, you have to really beleive in what you are teaching, and to really believe it, you have to have the experience in training.
RBZT works best for the schools that punish kids for defending themselves as much or more than they punish the bullies. While it doesn't address knives directly, certification as a graduate of RBZT should give the teacher or administrator the knowledge, wisdom, and confidence to fully apply any Zero Tolerance policy.
The program works with a RBSD or CQC class. The RBTZ students wear no padding and work as Reality-Based Striking Targets for the CQC and RBSD students. They are not allowed to fight back, but can go to an instructor to complain. The instructor will tell them things like "ignore them and they'll go away."
After the 5-day training is completed, all students who do not drop out get to be RBZT Certified.
