Side impacts collisions pose a great risk to children in crashes but information about the injury mechanisms is limited. The heights and weights of children vary widely and as a result, the injury patterns may vary across the pediatric age range. This study involves a case series of children in side impact collisions who were identified through Partners for Child Passenger Safety, a large child-focused crash surveillance system. The aim of the current study was to use in-depth crash investigations to identify injury mechanisms to children in side impact collisions. 93 children in 55 side impact crashes were studied. 23% (n = 22) of the children received an AIS > or = 2 (clinically significant) injury. In these 22 children, head (39%), extremity (22%), and abdominal injuries (17%) were the most common significant injuries. The cases revealed that serious injuries occur even in minor crashes. Cases that illustrate body region-specific injury mechanisms are discussed.