The purpose of this study is to discuss student and school factors, including cross level interaction, that cause inequalities in seven and eighth grade students' achievement in Turkish context by using national achievement test scores with a multi-level statistical approach. Our results are in line with most other studies with similar purpose. Our results show that approximately 17% of the variation in student test scores is explained by differences between schools, while the remainder of the variation is accounted for by within-school factors. Our results highlight that student-level variables alone explain nearly 73% of the between-school variance and approximately 19% of the within-school variance in student achievement scores. Our school-level variables explain a relatively small amount of the variation, approximately 5%. This has demonstrated that between- and within-school differences in student achievement are largely accounted for by the socio-demographic background of students. This is in line with the Coleman Study findings; the effect of school characteristics on student achievement was modest compared to the effect of students' socio-demographic characteristics. Our results also show that average parent education and income, full-day schooling, attending an urban school and the percentage of female students in the classroom mediate the relationship between student-level variables and student test scores.