Instructors typically consider material sequencing when developing courses; however, other factors may affect student performance. In this study, student performance when taking quizzes in sequential classes reveals that student performance on quizzes in the second class significantly drops when a quiz is given on the same day in the first class. No effect due the change in quiz sequencing in the first class was observed over the course of the semester. To an instructor, student requests to change the date of a quiz due to another quiz being given on the same date may be a legitimate request, and instructors should carefully consider course requirements sequencing in back-to-back classes.