The COVID-19 pandemic has significantly impacted the mental health and well-being of children and adolescents globally. This comprehensive narrative review synthesizes current research on the pandemic's psychological effects on young people, examining emotional distress, behavioral changes, sleep disturbances, educational disruptions, and the exacerbation of pre-existing mental health conditions. A systematic literature search was conducted using PubMed, MEDLINE, PsycINFO, CINAHL, and Web of Science, covering articles published from January 2020 to December 2024. Studies focusing on children and adolescents (aged 0-18 years) that examined mental health outcomes related to the COVID-19 pandemic were included. Data extraction was performed using a standardized form, and a narrative synthesis approach was employed to analyze and integrate the findings. Key findings reveal a substantial increase in anxiety, depression, and post-traumatic stress disorder among children and adolescents during the pandemic. School closures, social isolation, and disrupted routines have contributed to these mental health challenges. Sleep patterns have been notably affected, with delayed bedtimes, increased sleep disturbances, and a higher prevalence of insomnia and nightmares. The pandemic has widened educational disparities, particularly affecting children from disadvantaged backgrounds. Individuals with pre-existing mental health conditions have experienced exacerbated symptoms and faced challenges in accessing care. Various interventions, including cognitive behavioral therapy, social-emotional learning programs, and digital mental health support, have shown promise in mitigating the pandemic's psychological impact on young people. Children were more affected, as they faced a global crisis for the first time with limited coping skills. Disruptions in routine, social isolation, and family stressors heightened anxiety, depression, and behavioral issues, making them more affected. This review emphasizes the need for continued research, targeted interventions, and policy development to address the long-term mental health consequences of the COVID-19 pandemic on children and adolescents.