It's interesting what you think "common problems" are and the assumptions you make as to the solutions. I'll answer (1) such that a perspective into the vastly differing make-up of social and psychological profiles can be seen, then explain.

1) Castigate him for not leaving the other kid worse off, demand to know why he didn't see it through to the end, then ask him why he's confident enough in himself to wear a bracelet that provokes an ass-kicking but not confident enough to have his dad know who he is.

But it wouldn't happen unless someone else had been raising my kid.

I grew up in rural New Mexico in a peculiar little town with some history to it.. Said town is surrounded by abject poverty and violence. There's an element of Apartheid South Africa to it; everyone in town is white and has a Ph.D (two kids I went to high school with had parents with Nobel prizes) and everyone who cleans the bathrooms and restocks the grocery store shelves is brown and couldn't afford college (presuming they finished high school). The Espanola valley is one of the very few places in the United States that a white kid can experience prejudice; the consolation is that the Hispanics and the Indians hate each other more than they hate you.

My grandparents lived in the Espanola valley from 1948 until their deaths last year. My father attended elementary school in the Valley until the tide of rising violence forced his parents to drive him the 30 miles to school every day (one of them worked as a phone operator for Los Alamos National Labs; the other was a union plumber who did some of the work on the nuke shots in Nevada). The experience was formative on him and, as a result, formative on me.

I was watching an ABC Afterschool Special in 1st grade. My father, who had a habit of coming home for lunch at 1pm so he could drink 4 beers and sleep until 3 so he could go back to work until 7 or 8 and thus avoid my mother, observed Hammerman utter those famous words, "I'll see you after school."

My father observed this with some interest, then said:

If anyone ever says "i'll see you after school" to you, you say "no, you'll see me NOW" and you swing for his nose as hard as you can. And you don't worry about the pain when he hits you back, you keep hitting that kid until he's on the ground, and you don't stop until a teacher pulls you off. And you don't worry about getting sent to the office or anything like that, you make sure everybody knows that picking on you is too expensive to bother with because you want everyone around you trained before they start carrying knives.

It was an interesting lesson, particularly in the context of pre-adolescent socialization. The typical "avoid trouble/learn to get along/trust in adults" mantra was completely absent, instead replaced with "and they shall know us by our trail of dead/if you're going to play, play for keeps". Further, it emphasized that if you are comfortable with violence and ready to accept the consequences (which, when you're seven, are virtually nil), you will automatically defeat those who are not.

More than that, my mother taught at every alternative medicine school in Northern New Mexico. We were constantly surrounded by LGBT. I went to a lesbian wedding at nine. Being gay just wasn't a thing. I'd be far more worried about the empty sloganeering of a rainbow bracelet than I would by my son's sexuality; one wears colors because one has pride and any kid who will don the uniform but not come clean to his parents is a kid who has bigger secrets than his sexuality. I'd be far more concerned to see my daughter checking out The Fountainhead than I would seeing her check out other girls.

So... right from the bat, your theoretical questions are simply alien to my experience. The rest of them, quickly:

2) I don't leave my laptop anywhere.

3) I'm not dating their friend and I'm not going to let them ruin my evening.

4) See (1).

5) I'll bet it slows me down.

6) Become an officer.

7) Why should I give them pie when I can simply walk away?

* * *

The problem with hypotheticals is they are never complete, and everyone who answers them fills in the missing pieces from their experience. A lot of yours touch on experiences I've been through, so they aren't thought-provoking, they're memory-provoking. In many cases they're null - between my sister and I high school involved about nine wrecks, three of which we were driving in, one of which involved ambulances, hospitalization and a six figure insurance settlement, and nobody did any crying. It can be a fun exercise, but in order for it to be open-ended enough to be applicable to a large enough cross-section it has to be vague and if it isn't vague, it's going to be irrelevant to a lot of people.