if you're a good student and you've been keeping up then you probably don't need in-class instruction anyways and you can probably just write the exams like nothing happened. the schools should have that option available, allowing the best students to still get letter grades based entirely on their exam scores. if they're lucky - and next year isn't cancelled anyways - then they should get over this without much more than a hiccup.
slower students that require attention from the teachers, and/or haven't been keeping up, and can't pass an exam in these circumstances should be given the opportunity to repeat without it affecting their gpa.
so, what should it say on the transcripts?
it should say something like CANCELLED.
and, where necessary, students should be refunded entirely.
i know that i wouldn't want to pay for a grade that says PASS. i'd feel ripped off...