The physiological and anatomical features of the immature skeleton mean that lesions in it must be considered quite separately from lesions in the adult skeleton. As ossification progresses, the various anatomical regions of the developing bone are subject to changing biomechanic characteristics, leading to childhood-specific injury patterns. Since this issue is dedicated to fractures in childhood, this article takes the form of a short review of classification systems used for common pediatric fractures; there is also a short preface describing the anatomical-biological properties of the skeleton in childhood.