Okay, I understand what you're saying. You're asking if you qualify for the refundable portion of the AOC, and what constitutes a full-time student. According to IRS Publication 17, a full-time student is defined as follows: "A full-time student is a student who is enrolled for the number of hours or courses the school considers to be full-time attendance." IRS Publication 970 further states that, for the AOC, enrollment must be for "at least one academic period beginning in 2016 (or the first 3 months of 2017 if the qualified expenses were paid in 2016). . ."
Basically it's saying that your school decides what is a full-time work load. I think back to my college, and it considered 4 classes per (non-summer) semester to be full-time. And 4 classes meant 12 credit hours.
How many hours were you taking?
