Germ cell tumors (GCTs) are cancers of the testis, ovary and extragonadal sites that occur in infants, children, adolescents, and adults. Post-pubertal (type II) malignant GCTs may present as a seminoma, non-seminoma or with mixed histologies. In contrast, pre-pubertal (type I) GCTs are limited to (benign) teratomas and (malignant) yolk sac tumors (YST). Epidemiologic and molecular data have shown that pre- and post-pubertal GCTs arise by distinct mechanisms. Dedicated studies of the genomic landscape of type I and II GCTs in children and adolescents are lacking. Here we present an integrated genomic analysis of extracranial GCTs across the age spectrum from 0-24 years.