We claimed the AOC on 2016 taxes for two students not fully understanding the credit terms. Both students were high school students taking dual enrollment classes and both rec'd 1098T forms for a small amount paid to the community college. We followed Turbotax instructions for entering 1098T info without realizing it would count as 1 of the 4 eligible tax credit years. Since they haven't begun college yet we would like to remove the small AOC credit from 2016 and so that we can have the 4 tax years AOC claim eligibility for when they are actually college undergraduate students. We would owe the IRS the difference since we received a tax refund that year. Can we amend using the 1040X form? And do we include interest with our payment? I hate to lose the year of eligibility over such a small amount that was actually claimed.