You have to adjust, on your return, for what she uses on her tax return for the credit.
You also have to adjust for any scholarships shown in box 5.
At the screen where you enter expenses (on your return); under adjustments, enter the box 5 (1098-T) amount in the "Tax-Free assistance" box and enter the amount she used for the credit in the "Other adjustments" box.
Typically she only uses $4000 of the box 1 (1098-T) for the American Opportunity credit.
