The inherited model of schooling based on same-age tutor groups is not only wrong but anti-learning and unsafe. When examined from a systems perspective, the assumptions are revealed. This explains why schools fail to respond to reform and why reform is the wrong approach. It blames the same-age structure as the direct cause of bullying, poor parent partnership, mental health issues and more, pointing out the system's separation from psychology and child welfare. When schools adopt a mixed-age system (tutor groups / home-groups mixed by age) these adverse effects are resolved. The book calls for wholesale change to the way schools organize relationships and issues of connectivity. The author uses insights and research from his work with hundreds of schools worldwide transitioning from the same-age system to one based on mixed-age. This book rejects the use of pro-social programs (add-ons and fixes) in favor of one able to design in empathy, emotional intelligence, and character.