We're teaching our children to respond appropriately to conflict—in the situation above, either one of them can deescalate by approaching the conflict reasonably. He could have avoided it altogether by asking nicely for her pencil. She could deescalate by recognizing that he really wanted her pencil and making a trade that they both are happy with. It's hard for them to do because their escalatory actions feel more immediately effective at bringing "justice", but they don't work out in the long run.

The cycle of childishness isn't going to be solved by a post that triggers an internet mob, that's just another childish response in the cycle.