If you are claiming the student as a dependent on your tax
return, then you are the one that can claim the American Opportunity Tax Credit. To not claim the credit, do not enter the
education information.
Consider this though, if the student has filed a tax return
claiming the credit, then the return was not filed as if he/she was being
claimed as a dependent on another person’s return because the credit would not
have been allowed. The student’s tax
return will likely need to be amended to correct these things. Then your return can be filed claiming the
student as a dependent and including the education information to claim the
credit.