Heh, I pretty much went to a school like this as a kid. After I got expelled from all the others in the district. I had excellent grades, but being retarded I was always bullied heavily...when it got physical (and it always did) I violently defended myself.
With size strength and experience on my side I could and did do serious harm.
There's a troubling and ironic story there, but that's another topic.
It was a small school (~400 students) built in blocks, each block 2 rooms connected by a small hallway, one shared bathroom on one side of the hallway and an office/security station opposite that. Bars on the reinforced windows and locked steel doors everywhere. They had 20ft fences around the entire school and locked gates at the entrance.
They had classes setup in a controlled way to limit the maximum number of kids moving/in a group at once. There was no free for all between classes, you moved in a pattern from one half a block to the next then to the next block in a tiered pattern. Movement between blocks was along a small path around each block with entrances on only one side each block. When you needed to move multiple blocks from the end you moved along the back with no entrances and no other groups.
No large "communal" places, no cafeteria, even the gym was split into multiple rooms. They also controlled the class groups, they could pull people out of one class group and move them to another. They required parents to participate at the school as well. They had to spend at least 1 full day every other week. Helping a teacher, cleaning, participating in "guard duty", or even just watching their kid.
Seeing the school in that video, clearly they are far to open and liberal with the kids. When they are that bad you need a heavy hand and strict enforced rules. Take away all their freedoms, make them behave. That kid messing with the sharpener? The kid wandering around screwing with the computers misbehaving and trying to damage property? Absolutely no tolerance. Sit down shut up or we will make you. We can and will remove you and lock you up. This school is absolutely your last chance, we can turn your friends against you, and we can even be hard on your family.
You fail here and you have nothing and nobody. Show them what that is really like. That worked well where I went, and I agree with it.