Two cases: taking classes online while visiting Korea, and visiting Korea without taking a summer term
I’d like to know whether taking classes online while visiting Korea on student status, versus visiting Korea without taking a summer term, are treated the same or differently. And if possible, since I haven’t graduated yet, I’d like to know if I can re-enter the U.S. using just my I-20, or if I need other documents as well.
USCIS doesn’t clearly distinguish or treat cases differently based on whether classes were online or offline — after all, this is normally an offline school. If your I-20 is still valid before graduation, you can still enter the U.S.
However, if your F-1 visa stamp has already expired, even if your I-20 is valid, you’ll need to obtain a new F-1 visa stamp.