Social relationships in the school context -- particularly teacher-student relationships and peer relationships -- are related to students' positive attitudes toward school, and consequently are of great importance regarding various aspects of learning and instruction. This can be concluded from studies that examine the influence of social integration on motivation, learning emotions, and positive attitudes toward school as an institution. Additionally, social relationships are closely related to the teacher's style of instruction and student perceptions of the learning environment provided. However, there is little research so far, on the extent to which positive social relationships mediate correlations between aspects of teaching quality i.e., classroom management, and students' positive attitudes toward school. Both classroom management and school-related social relationships are constructs that are assumed to be perceived similarly by students within one school, who experience similar conditions in regard to the intensity and frequency of common lessons. However, there are few research findings regarding shared assessments of classroom management and it's correlations with teacher-student relationships by students within one school or class, and to date no results regarding the shared assessments of peer relationships. Therefore, the current study aimed to examine the correlations between students' individual and aggregated assessments of social relationships in school and classroom management, with their positive attitudes toward school. The sample consisted of N = 453 polytechnic school students in Upper Austria, from which a weighted dataset was derived. The findings from multilevel mediation analyses support the assumption of the mediating role of both teacher-student relationships and peer relationships regarding the correlation between classroom management and students' positive attitudes toward school. However, significant correlations were found only at the individual student level.