In increasing numbers of classrooms worldwide, students use digital learning software. However, we know little about the trajectories of usage and the performance within such digital learning software over the academic year. This study analyzed real-world longitudinal data from a mathematics learning software used in classrooms in Germany and the Netherlands (6,000 students who worked on >23 million problems). We evaluated students' usage and performance trajectories across an academic year by examining the percentage of students using the software, worked-through problems, active days and weeks, as well as performance. Our results indicate a decline in both usage and performance over the course of the academic year, with overall lower usage in Germany than in the Netherlands. Our findings highlight the need for further research into the factors maintaining or increasing the usage of and performance in classroom-integrated digital learning software over extended periods.