This paper focuses on the impact of school factors on student achievement due to differences in family backgrounds. Based on the principle of diminishing effects of school investment in children's achievement, this study built a model that includes individual characteristics, family characteristics, and school characteristics. Family and school variables were incorporated into the model. The subjective effort in children's individual study and family investment and effort in education were controlled. Using data on elementary school children from 20 counties in Gansu Province, this study found that parents' level of education and family income and indices of school quality have a significant positive relationship to children's achievement. However, an increase in school investment will shrink the score differences caused by differences in children's family backgrounds. The policy implications are that increased educational investment in impoverished rural areas has an even more significant positive effect on the achievement of children from disadvantaged family backgrounds. [English translation © 2016 Taylor & Francis, Inc., from the Chinese text "Jiating, xuexiao yu ertong de xuexi chengji -- jiyu Gansu Sheng nongcun diqu de yanjiu" by Sun Zhijun, Liu Zeyun, and Sun Baicai. Translated by Jeff Keller. Originally published in "Beijing shifan daxue xuebao (shehui kexueban)" [Journal of Beijing Normal University (Social Sciences Edition)] 2009, no. 5, no. 215.]