Climate change, COVID-19, and the Russia-Ukraine War are some of the great challenges of our time. These global crises affect young people in a particularly vulnerable phase of their lives. The current study aimed to assess the impact of these crises on mental health (depression, anxiety, and health-related quality of life) in secondary school students in Germany. Furthermore, we assessed known predictors of mental health, such as socio-economic factors, individual life stressors, and resilience factors (self-efficacy, expressive flexibility) as covariates. In our sample of 3998 pupils, pandemic- and climate-related distress were linked to greater depression and anxiety and reduced health-related quality of life. War-related distress was associated with greater anxiety. Critically, these associations remained significant after controlling for all covariates, supporting the incremental predictive value of the crises measures. The study reveals a significant impact of the crises on the mental health of the current generation of adolescents. As such it suggests that mental health policies should include interventions that help youth to cope with the stress caused by the crises.