See this Q&A from the IRS which describes an exception for a graduate student to receive the American Opportunity Credit:
Q13. If a student was an undergraduate during the first part of the taxable year and became a graduate student that same year, will the student qualify for the American opportunity tax credit?
A. If a student has not completed the first four years of post-secondary education as of the beginning of the taxable year, and has not claimed the Hope scholarship credit and/or the American opportunity tax credit for more than four taxable years, the student can claim the American opportunity tax credit for qualified expenses paid during the entire taxable year.
Here is a link to the IRS Q&A publication: <a rel="nofollow" target="_blank" href="
https://www.irs.gov/uac/american-opportunity-tax-credit-questions-and-answers">https://www.irs.gov/u...>
