Researchers from Germany studied how children aged 10 and 12 divide resources between two people who had different levels of effort and need. The study asked a straightforward question: when one person works harder but another needs more help, what does fairness look like?
The sample size and full methodology aren't specified in the source provided, but the findings reveal a clear developmental pattern across these two age groups.
Ten-year-olds think about one fairness rule at a time
At age 10, most children couldn't hold two fairness ideas in mind simultaneously. They either gave more to whoever needed it most, or more to whoever worked hardest—but rarely considered both factors together. This isn't inflexibility or stubbornness; it's simply how their brains worked at that stage.
By 12, children can weigh need and effort together
By age 12, significantly more children could balance multiple fairness principles at once. They could think: "This person worked hard AND is struggling, so I need to weigh both when deciding." This represents a genuine cognitive leap—their developing brains gained the capacity to juggle competing moral ideas and find a balanced answer.
Brain development drives fairness thinking, not parents or school prestige
Surprisingly, parents' own fairness decisions didn't predict how their children would decide. The research suggests that natural cognitive development—how children's brains mature—is the primary driver of these changes, not parental modelling or school environment. School type had only a small effect, and only in extreme cases of need. This means your child's moral reasoning grows largely through brain development rather than through copying what you do or attending a particular school.
Help your child's fairness thinking develop naturally
- Expect rigidity at 10 and flexibility at 12—it's brain development, not defiance or character flaw.
- Present fairness dilemmas with multiple competing values (effort versus need) to let older children practise balancing them.