I'm in the specification part of a project and i have to make use cases but i don't understand how to translate this scenario. The project is: Students and teachers have to check in with a card in every class and the system counts presences and absences, if the teacher doesn't check in it doesn't count any absences because it's like there was no class. When the student reaches 25% absences the system sends an email to the teacher and student warning them.
My question is should the act of "checking in" be the same use case if it has different repercussions for each actor? How do i represent that if the teacher didn't check in then there's no class?