If you believe the DOE propaganda that the New York City schools are safer, then I have a bridge in Brooklyn to sell you, Sure, the DOE statistics do show a reduction in criminal actions but that's because many criminal actions are subject to the school Principal determining the severity of the crime.
For example, school weapon arrests have skyrocketed by 35% so far this year. A total of 746 weapons have been confiscated this year, compared to 552 last year. Despite the increase, the actual criminal arrests were down because under Bill de Blasio many students caught with knives and box cutters were not criminally charged, or even given a summons. Instead, it was left up to the discretion of the school administration to determine the punishment, if any. For example, "warning cards" rather than arrests are the newest fade and instead of suspension its restorative justice. No wonder, most students feel more unsafe than in previous years.
Despite the rise in weapons in schools, only 3 additional schools have metal detractors and only 6% of all schools have them. You can read more about this Here and Here.
The Bill de Blasio/Carmen Farina weakening of the student discipline code, the allowing of cellphones, and the reduction in suspendable offenses has resulted in schools being less safe. Just ask the students!