The goal of this clinical trial is to evaluate the impact of SCThrive (a behavioral self-management intervention) on patient activation, self-management behaviors, daily functioning, and emergency room visits in 260 adolescents and young adults with sickle cell disease (SCD) ages 13-21 receiving care at 1 of 4 pediatric SCD clinics. The main question\[s\]it aims to answer are: * Does SCThrive improve patient activation? * Does SCThrive improve self-management behaviors, daily functioning, and decrease emergency room visits? * Are any improvements maintained 3 months after treatment? Participants will complete self-management related surveys before, after, and 3 months following their participation in an 8- week, virtual group intervention with an accompanying mobile app (SCThrive). Researchers will compare outcomes for participants who receive SCThrive and participants who receive uniform standard care (SCHealthED which = standard of care plus SCD educational text messages) to see if there are differences in patient activation, self-management behaviors, daily functioning, and emergency room visits.