This article presents GISMO, a novel, open source, graphic student-tracking tool integrated into Moodle. GISMO represents a further step in information visualization applied to education, and also a novelty in the field of learning management systems applications. The visualizations of the tool, its uses and the benefits it can bring are illustrated through a detailed case study of an online course. GISMO provides visualizations of behavioral, cognitive and social data from the course, allowing constant monitoring of students' activities, engagement and learning outcomes. (Contains 11 figures and 1 note.)