This study aimed to assess the effectiveness of the "Family and Parenting Support Program" (PSFP) for children aged 6–11, compared to a minimal intervention involving parenting information, using repeated measurements: before the intervention (T0), 1 month later (T1), and 6 months later (T2). The goal was to measure changes in children’s behaviors and psychosocial skills, changes in parenting practices, parental anxiety/stress and children’s well-being, as well as the amount of screen time spent by children. This evaluation was conducted by Santé publique France between 2017 and 2019 in approximately twenty cities across France (including two on the island of Réunion). Significantly different effects between the PSFP group and the Control group, favoring the PSFP group, were found one month after the end of the program (changes between T0 and T1) regarding children’s hyperactivity, children’s behavioral disorders, parental engagement, increased child well-being, and parents’ mental health. These effects persisted 6 months after the intervention (change between T0 and T2) regarding behavioral problems and the child’s well-being. Process indicators confirmed the successful adaptation of PSFP in France. Today, PSFP 6-11 is implemented in 12 French regions. To ensure the program’s quality and its long-term sustainability across the country, a protocol for monitoring its rollout has been established by Santé publique France.