Poor attitudes towards disability held by one's peers can negatively impact the social experiences of students with exceptionalities. Fortunately, educational intervention efforts can serve to enhance children's attitudes towards disability. This quasi-experimental study tested the effectiveness of the Tripartite Intervention (TI), a 12-lesson educational intervention aimed at improving students' attitudes towards disability. Two Grade 4 classes from a large rural school in Southwestern Ontario made up the control and experimental groups. The CATCH scale was used to measure students' attitudes towards disability before and after the intervention. 2 × 2 mixed ANOVAs were calculated to measure the effectiveness of the intervention. There was a significant main effect for time, but a non-significant interaction effect when global attitude scores were examined. A significant interaction effect was found, however, for the cognitive dimension. These findings indicate that the TI had an impact on how students thought about disability. Determinant factors were also examined. Having a family member was associated with more positive attitudes towards disability, whereas self-reported gender and friendship with someone who has a disability were not. Replication studies on the effects of the TI with larger and more diverse samples are needed.