Having officiated a few sports, I'll make a couple comments.
Obviously these are inner city kids.
I did a soccer game with 1 of the Newark magnet schools involved. Those kids were some of the best behaved kids I've officiated & I let their coach know it. He remarked that these kids were 'chosen' to attend the school & indicated that it was a privilege they were given. Made it seem like, they better behave or that privilege could be forfeited. Regardless, the kids seemed like good kids.
I know that some, if not all, urban school districts receive federal money, often IMHO excessive. Some of this money is spent on security, including police present at games. Most schools have that at home games, but some schools like New Brunswick send 2 officers + additional security to ALL away basketball games (could be other sports as well). I witnessed a girls BB game with maybe 50 people in attendance, half of whom seemed asleep, where they had these out of town officers present. To me, it was a waste of taxpayer money. The home team should be responsible for security except in instances of real rivalries, where large fan bases can sometimes get rowdy, or in cases where 2 schools have a history of trouble between themselves. I'm very surprised that in Newark there wouldn't be any officers present. Also seems likely spectators may have been responsible for most injuries, as was the problem with the Howell hockey fiasco.