During middle childhood from ages 7 to 12, children experience significant physical, cognitive, social, and emotional development. Physically, children grow taller and stronger through skeletal and muscular changes. Cognitively, most children attend school for the first time and learn in structured environments. Socially, peers become increasingly important as children spend about 40% of their time with friends, navigating social hierarchies. Emotionally, developing independence can cause tensions with parents while forming an individual identity and self-esteem is an ongoing process.