The 1098-T can be a bit confusing.
Use it as a guide, but also refer to your own records.
Schools report Box 2 "Amount Billed by the school"
You get credit for what you PAID to the school.
Often the school will bill in December for classes that start the next year.
Claim what you paid in the year you paid it.
Next year, schools will be required to report Box 1 "Amount the school received" which should make things less confusing.