With the strike of COVID-19, all schools transitioned to online learning. Studies conducted during the pandemic indicated that many instructors and students expressed that their experience has degraded compared to the regular face-to-face class meetings. During remote classes, students' attention spans were observed to be lower than ever before. Additionally, many students expressed that they are struggling with their learning and feel disconnected from the class and their classmates [1]. As a result, class attendance also dropped to unpreceded levels. Currently, although most of the schools returned to in-person instructions, thanks to the declined infection rate after the development of different vaccines, online and hybrid class meetings are still an option for conducting a class, especially for those students who might contract COVID during the semester. In this work, we study the students' performance in a linear control course across three different cohorts: pre, during, and after the pandemic. Statistical analysis of students' exam scores is used to infer whether the online experience significantly affected the students learning or not. We use data from the course offering in fall 2019, fall 2020, and fall 2021, where the taught modules and final exams were kept the same. In addition, while the homework assignments were not identical, they were of the same level of difficulty and coverage, so we extend the study to include the students' performance using the homework assignments too. To study how the same student cohort reacts to different class meeting modes of the same subject, we study the students' perception of the change in teaching mode, from in-person to online, during the offering of a feedback control course in the summer of 2022. In that semester, with the same body of enrolled students, we taught the first half of the semester in-person and the second half online. We fixed the class activities and teaching pedagogy throughout the semester. We compared students' scores, participation rate, and attendance rate in the in-person modules vs their scores in the online modules. The statistical analysis of student scores in the two courses showed that students' performance in remote setup is significantly higher than, or at least the same as, student performance in in-person offerings of these two courses. Finally, we used an anonymous student survey to capture students' perceptions of the change in the teaching mode during the semester. Students indicated that the transition to remote learning made it hard to stay engaged in class. However, class activities and class recordings helped to mitigate these shortfalls.