The purpose of the study was to describe the frequency of diabetes self-management activities, processes, and goals among early adolescents. In addition, differences in self-management by age at diagnosis and duration of diabetes were explored. A cross-sectional design was used to analyze baseline data from 320 adolescents with T1DM enrolled in a multisite clinical trial. Participants completed questionnaires on demographic/clinical characteristics and self-management. There was a transitional pattern of self-management with a high frequency of diabetes care activities, problem solving, and goals and variable amounts of collaboration with parents. After controlling for therapy type and age, youth with short diabetes duration reported performing significantly more diabetes care activities than individuals with a longer duration. Individuals with short diabetes duration had more frequent communication than individuals with a longer duration, which was associated with diagnosis in adolescence. Among those diagnosed as school age children, those with short diabetes duration reported significantly more diabetes goals than those with a longer duration. A more specific understanding of self-management may help clinicians provide more targeted education and support. Adolescents with a long duration of diabetes need additional self-management support, particularly for diabetes care activities and communication.