Burnout refers to characteristic stress symptoms resulting from chronic overload at the workplace. However, increased stress and strain are observed already in adolescents in the context of school. Previous work shows that school burnout is associated with female gender, immigration background, higher academic achievement, and increasing grade level. We aimed at replicating these findings and extending them by investigating subjective stressors in a survey among 502 German high school students. Higher burnout scores related to all previously reported predictors, as well as the subjective stressors “homework” and “pressure to perform at school”, explaining up to 24% of the variance in burnout scores. These findings provide valuable evidence for effective prevention measures, optimal timing and target groups to combat school burnout.