This data note presents a dataset from a 10-day experience sampling study conducted among middle and secondary school students in 2022. The dataset includes a brief start-up survey in addition to 40 momentary assessments, enabling analysis of both inter- and intraindividual processes. The start-up survey includes validated measures on students’ perceptions of school-related support from family, peers, and teachers, general self-efficacy, and academic self-efficacy, as well as items on school enjoyment and school absenteeism. The experience sampling data includes items related to positive and negative emotions, lecture characteristics, perceived teacher style, peer relationships as well as sleep quality, breakfast, school readiness, and school day satisfaction. Data were collected using the "RealLife Exp" mobile app. Multiple procedures were undertaken to validate and confirm the reliability of the dataset. The methodological approach utilized for gathering the data featured in this dataset allows for a nuanced analysis of individual and contextual influences along with lagged effects on school well-being, with the potential to discover previously overlooked patterns and trends.