No, you do not enter that anywhere on your tax return. It is totally tax free. The $5250 limit, for tax free employer reimbursement, does not apply to college employees. What you have is "Tuition reduction", rather than an employer "tuition reimbursement" plan. It is treated differently. Another way of thinking about it is: you are getting a discount on the price.
Reference: https://aronsonllc.com/qualified-tuition-reduction/
Also see page 8 of IRS Pub 970 https://www.irs.gov/pub/irs-pdf/p970.pdf
