Brain tumors collectively represent the most common solid tumors in childhood and account for significant morbidity and mortality. Until recently, pediatric brain tumors were diagnosed and classified solely based on histologic criteria, and treatments were chosen empirically. Recent research has greatly enhanced our understanding of the diverse biology of pediatric brain tumors, their molecular and genetic underpinnings, leading to improved diagnostic accuracy and risk stratification, as well as the development of novel biomarkers and molecular targeted therapies. For subsets of patients, these new treatment options have already resulted in improved survival and decreased treatment toxicity. In this article, we provide an overview of the most common childhood brain tumors, describe recent key advances in the field, and discuss the therapeutic challenges that remain.