This is a great addon!
I found two problems, I make here a notice, perhaps I can assist a little to the development.
1. Teachers can see attendance in student report all courses view for all courses, not just their courses. I think It would be better when they could see the attendance of a student just for their courses.
2. I translate the addon for Hungarian (I send it for the package, if I get an adress). I translate the statuses too (Present, Excused, Late, Absent), but on the settings page, there are the english ones. Ok, I can overwrite these, but it is easier for our teacher if they get the hungarian translation as default. I look at the code, the names (Afull, Efull, Pfull, Lfull) in the language file aren't in any php file. I think it would be very good too, if I can set the grades as default for our teachers.
I uninstall then reinstall the activity with the translated hungarian language file and the second problem is resolved they strings are hungarian now. The 1. problem is a problem for me yet. I attach the hungarian language file.