Background: The association between early childhood psychosocial problems and poorer educational outcomes is well-documented, but the extent to which this association persists is less understood. The current study assessed the correlations between first-grade psychosocial functioning and educational outcomes through eighth grade in a large longitudinal sample of Chilean students. Methods: The Pediatric Symptom Checklist-Chilean (PSC-CL) and Teacher Observation of Classroom Adaptation Re-Revised (TOCA-RR) assessed psychosocial functioning for 9736 students who were screened four times from first through eighth grade through the Skills for Life program. Adjusted linear mixed effects models assessed the association between first grade PSC-CL and TOCA-RR risk and third, sixth, and eighth grade GPA and school attendance. Results: First-grade PSC-CL and TOCA-RR risk both significantly predicted lower third, sixth, and eighth grade GPAs; all p < 0.001. The relationships between first-grade psychosocial functioning and later school attendance rates were less consistent but still significant at certain time points. Conclusions: First-grade psychosocial risk was persistently associated with lower academic performance in a longitudinal sample of Chilean students followed through elementary and middle school. Implications for School Health Policy, Practice, and Equity: Early school-based psychosocial screening and follow-up interventions have the potential to improve students' long-term educational outcomes.