<![CDATA[Although academic achievement and interpersonal relationships are recognized as closely related components of elementary education, limited evidence has examined these relationships simultaneously among young Indonesian students. This study investigated whether relationships with parents, teachers, and peers differentiated levels of academic achievement among elementary school students. A total of 240 fourth- and fifth-grade students were classified into three achievement groups based on report card scores: adequate (<80, n = 89), remarkable (80–84.9, n = 83), and exceptional (≥85, n = 68). Interpersonal relationships were measured using a 21-item Likert-scale questionnaire ranging from 1 (strongly disagree) to 4 (strongly agree). Data were analyzed using confirmatory factor analysis, one-way ANOVA, canonical discriminant analysis, and multinomial logistic regression in SPSS and SmartPLS 4. The results showed no significant differences among achievement groups in parent relationships, F (2, 237) = 0.38, p = .684, ηp² = .003. Peer relationships showed a non-significant tendency, F (2, 237) = 2.53, p = .082, ηp² = .021. In contrast, teacher relationships differed significantly across achievement levels, F (2, 237) = 3.33, p = .038, ηp² = .027. Canonical discriminant analysis further indicated that the three relationship dimensions jointly differentiated the achievement groups, Wilks’ λ = .940, p = .023. Overall classification accuracy reached 43.8%, with the highest accuracy obtained for the exceptional-achievement group. These findings provide comparative evidence that teacher-student relationships are the strongest and most consistent interpersonal differentiator of academic achievement, while parent and peer relationships show weaker distinctions across achievement levels.]]>
