The cerebellum is a brain structure that has been studied for many years, but its anatomy and physiology are still widely debated. While the importance of the cerebellum has been demonstrated in the motor domain, mainly through neuroimaging studies, its involvement in cognitive functions remains a matter of debate. In this project, we carried out a lesion study on children operated for cerebellar tumors. Cerebellar tumors are the most common brain tumors in children and lead to heterogeneous post-operative motor and cognitive deficits, ranging from minor deficits to major ones drastically affecting the children's life. Here, we aimed to understand these observations more in-depth. We considered children lesions’ properties (volume, location, histological type), and clinical motor and cognitive data obtained through neuropsychological tests (perdue pegboard, intelligence scale, etc.) and performed a voxel-based lesion symptom mapping (VLSM) analysis to better understand the cerebellum joint involvement in motor and cognitive functions. The preliminary analyses showed that the anterior and posterior vermis of the cerebellum in both motor and cognitive functions. Moreover, the type and number of damaged cerebellar nuclei (dentate, interposed, and fastigial nuclei), lead to different deficits. A high-level task requires the integrity of more nuclei than a low-level task.