KIDS FIGHTING: WHAT TO DO IN THE MOMENT B
Sometimes you see your kids fighting over a toy and you don't know what happened before you got to the fight. You don't know who should get the toy.
For those times, you can try having them play rock-paper-scissors or have them flip a coin to see who gets the toy.
I would not introduce rock-paper-scissors or flipping a coin during the heat of the conflict. Your kids' elevated emotional states will inhibit them from focusing on learning a new skill.
At a family meeting, you can say, "One of the tools you have for settling fights is to do rock-paper-scissors or flip a coin." Then I would suggest practicing the games a few times. I would talk about how you can't change your hands in the rock-paper-scissors game after you see the other person's hands. If needed, they might need to hold their hands behind their backs. "But if you all choose to play either of these games, you have to agree to let the winner of the games get the toy. If you lose, you have to let the other person get the toy. Do you both agree to do that?"
If the child who loses the game stays under control, make a big deal out of it. "Wow! Even though you didn't win the toss, your body and face are calm! That's called having self-control. "
I use this in the classroom a lot if I see kids fighting and most like this method.