After entering the 1098-T, carefully follow the TurboTax (TT) interview. You will eventually reach a screen to enter book expenses.
If you missed it the first time,
In TurboTax (TT), enter at:
Federal Taxes Tab (Personal for H&B version)
Deductions & Credits
-Scroll down to:
--Education
--Education Expenses and Scholarships (1098-T). Click Update (or Start)
The next screen is: '"Your education expenses summary". Click Edit
The next screen is: '"Here's your education summary". Click Edit next to "Other Education Expenses"