The kids often don’t seem interested in our conception of what’s fair. Usually, they want it their way, and they want it now. What to do when there’s a disagreement?
Perhaps you want to teach kids that coming to a fair solution is always best. But if you interfere too much, they may never internalize the notion of fairness, and instead become accustomed to having solutions handed down to them.
On the other end of the spectrum, you could just let them fight everything out tooth and nail. Set up a little ring for their battles and encourage the adults to place side bets. Maybe they’ll work out the whole fairness thing on their own!
In my experience it’s best to take the middle ground. Let the kids try and work things out. Really try and hold back the urge to intervene. I think these days, parents intervene too soon (myself definitely included), depriving the kids of an opportunity to learn something on their own.