Supratentorial intraventricular tumors are not frequently encountered in childhood. One of the most frequent intraventricular glial tumors is the subependymal giant-cell astrocytoma, mostly associated with tuberous sclerosis. These tumors are diagnosed on computed tomography (CT) or magnetic resonance imaging (MRI) scans. They can occur isolated or multiple and operative resection is advised if these tumors cause symptoms, usually raised intracranial pressure due to obstructive hydrocephalus. However, the number of tumors can be much higher than seen on radiological examination making total resection of all tumors impossible. We demonstrate this with the endoscopic images derived during the endoscopic removal of a subependymal giant-cell astrocytoma obstructing a foramen of Monro in a 15-year-old boy with tuberous sclerosis.