本文旨在探討國中教育的選擇和社會化功能與學生自我概念之關係，而在實徵研究時以能力分班為探究焦點。文獻分析的結果，本研究建立一套涵蓋學生家庭社經地位、班級類別、學校社會化經驗及學生自我概念等四個變數的模型。並立意取樣三所實施能力分班的國中三年級學生前後段班各一班，以檢定各變數間之關係，和模型的解釋力。本研究獲致以下結論：一、前後段班學生的家庭社經地位指數、學校社會化經驗和自我概念均有顯著性差異；二、前後段班學生自我概念的形成，受到學校社會化經驗的影響；三、國中能力分班的結果有社會階層再製的現象；四、對學生自我概念的形成以社會化理論有較大的解釋力，而分配論的看法並未獲成立。本研究並根據研究結果，提出改進建議。

The aim of this article was to explore the relationship among the function of both educational selection , the function of socialization ,and the students’self-concept in Junior high school, focusing on ability grouping applied to empirical studies . Results of the analysis of the literature, this study established a model consisting four variables such as : family socioeconomic status, class category, socialized experience in school and the student's self-concept. The researcher selects one high achievement third-grade class as samples and one low achievement third-grade class respectively in three ability grouping schools, to test the relationship among the variables and the interpretation of the model. This study was to the following conclusions: First, there are some significant differences between high achievement class and low achievement class, such as family socioeconomic status, socialized experience in school and the students’ self-concept.Second, the formation of the students’ self-concept is influenced by the social experience in school. Third, the ability grouping leads to the reproduction of social class ; Fourth, the socialization theory has a greater explanatory power for the formation of students’ self-concept, and the allocation theory has not been proved. According to the study findings, recommendations for future improvement is hoped to be achieved.