Abstract Grade III anaplastic ganglioglioma is an aggressive, rare, and radiosensitive central nervous system (CNS) tumour. It is more common in males, with a ratio of 1.3 to 1. Its peak incidence is in the third decade of life. Only 10 cases were recorded in children in Colombia from 2000 to 2014, with a fatal outcome in spite of radiation therapy. This is a case of an adolescent, who began having headaches, with warning signs related to an arteriovenous malformation hindering the diagnosis of this rare tumour. This presented in its aggressive, multi-focus form. Knowledge of clinical manifestations of space-occupying intracranial lesions facilitates the assessment and treatment of affected children.