The COVID-19 pandemic posed a major challenge to universities. It forced them to face the urgent need to rapidly transform their traditional onsite teaching into an emergency remote teaching (ERT) model rather than being able to gradually introduce an effective transition to an online model. Based on a sample of 505 students enrolled in the course on Work Organization at the University of Murcia in Spain, this study analyzes the impact of implementing an ERT model on students' academic performance. Results show that students display superior academic performance in an onsite teaching-learning model compared to the online ones adopted during COVID-19. Findings also reveal that students' self-assessment activities enhance their academic performance--both in onsite and online teaching contexts--which implies that ERT model performance can be alleviated by adequately planning self-assessment activities during the course.