The study sought to identify family conditions and school actions associated with academic self-efficacy and emotional well-being of adolescents during the COVID-19 pandemic in Chile. School closures are likely to have affected students' sense of academic efficacy and emotional well-being by removing support factors such as teacher and peer support for both academic and social tasks. At the same time, family stressors caused by the pandemic are also likely to have affected children. Data were collected by a Chilean school district about the family conditions and well-being of 5th-12th-grade students (N = 1,941) during lockdown. Exploratory factor analysis and latent profile analysis were applied to parents' and students' reports about family processes and material conditions. Family profiles and school responses to lockdown were used to predict students' academic self-efficacy and emotions. Family profiles were mainly differentiated by parenting processes, material conditions, and parenting stress. Regression analyses showed that the family profile predicted students' negative emotions and low self-efficacy. Specifically, children of families with higher scores in all dimensions were less at risk of reporting low academic self-efficacy and negative emotions, but the two average profiles--with high and low stress--were not different in this regard. Student gender and age were predictors of negative emotions but not self-efficacy. In contrast to family factors, school actions during the pandemic did not predict academic self-efficacy and well-being. Results suggest that family processes continue to be relevant beyond early infancy. Implications for the targeting of policies to support parenting are discussed.