The tendency of kids to split up spontaneously into subgroups also explains the uneven success rate of programs that put children from disadvantaged homes into private or parochial schools.

• 孩子有自发地分裂形成小团体的趋势，这也说明了将贫穷家庭孩子放入私人或教会学校的计划为什么成功率参差不齐。