Adolescents with Type 1 diabetes (T1D) experience unique self-management challenges, which can lead to poor glycemic control and sequelae. School nurses may impact student self-efficacy behaviors for T1D management in adolescents. The purpose of this study was to determine the relationships among school nurse staffing patterns, measured by school nurse to student ratios, self-efficacy, and glycemic control in adolescents with T1D. The sample consisted of 89 parent-adolescent dyads. Adolescents aged 10-16 years old with T1D completed the Self-Efficacy for Diabetes Self-Management (SEDM) Scale. Parents completed a demographic questionnaire. Higher school nurse to student ratios correlated with better glycemic control and older age. Higher SEDM scores correlated with older age, and females scored significantly higher. Findings contribute new knowledge to the paucity of literature on school nursing and adolescents with T1D, with implications for nursing practice, education, research, and policy.