There are other options too. My situation is similar in some ways. I teach in an inner city public high school in Miami FL. That neighborhood, too is full of the bad guys. Most of the REALLY bad BAD GUYS are outside our perimeter. They have no interest in "school" for their own academic benefit. They like the school as a "customer base." The MS13 guys are easy to spot and avoid with all those tats. Of course I can't carry at school and my parking situation precludes then carry to or from as well.
But when things are really wild and wooly sometimes I take my plastic travel wrench
IMPACT KERAMBIT - SHOMER-TEC in my pocket or a SHARKEY marker from "Cold Steel."
Pocket Shark
Last year, a teacher was jumped in my hallway after school. He was tutoring the kids for FCAT on his own time. There was no security available after school there. He'd confiscated an iPod during his class that day and the female student had slapped him. She was given an outdoor suspension although she should have been arrested according to district policy, but the principal at that time was a wuss and didn't go that route. She came back after school and ambushed the teacher (sheep) outside his class which is right across the hall from ME. I usually stay late to grade my papers, but that day I was out sick with the flu. The perp brought her crack addict mom and her golden gloves boxer brother. They busted the teacher's jaw in three places. The next day the girl (student) shows up looking all innocent and stupid. She was THEN arrested on the spot. The teacher, never returned.
I was asked by my kids what I would have done and am I now "scared to come to work?" I laughed at that one. Out loud. I looked at my class who was waiting expectantly for my answer:
"Look, I'm too young to die and too old to get my butt kicked. So ... I'm just gonna kill ya." They were mostly stunned. But a few of my guys all kind of yowled and said:
"Yeah we sorta figured you'd say something like that! You GO, sir!"
Once I got a bad kid expelled and he made all sorts of DIRE threats. Nothin' I'd not heard before, especially when I was getting some dirtbags probation or parole revoked while I was a badged parole officer. I heard that stuff in court sometimes.
This case made the other teacher's afraid. I guess the kid had a "rep." So I started walking around school with a section of the Miami Herald rolled up under my arm. My Aikido Sensei had been working with me on this particular improvised weapon quite extensively and I felt very confident that I could use it to best advantage against one or more opponents any time they cared to step up. None ever did. Personal bearing is everything in my business.
"If you look like prey you WILL be eaten."