School performance is a key aspect for future professional and social success. The objective of the present study was to investigate factors associated with adolescents' school performance including sense of coherence (SOC) and oral health status. Three hundred eighty one schoolchildren between 15 and 18 years of age from the city of Campo Grande, Mato Grosso do Sul, Brazil, participated in the study. The outcome variable was school performance, assessed through the final grades of the Portuguese and Mathematics disciplines in 2013. Independent variables were sociodemographic data, self-perception of oral health, use of dental services and sense of coherence, obtained through a self-applied questionnaire. In addition, in a clinical assessment, the number of decayed, missing and filled teeth (DMFT index) was evaluated. Logistic regression analyses were performed, based on a hierarchical model. The mean age of students was 16 years; mean DMFT value 4.1, and SOC 44.5. In the final adjustment, the male subjects (p = 0.0021); those with the largest number of people residing at home (p = 0.0021) and weak SOC (p = 0.0005) showed an association with poorer school performance. In conclusion, school performance is a complex phenomenon associated with SOC and oral characteristics.