Not sure if you are qualify. Someone says,

"Any university (State funded) student, you can get 15% off your monthly if you are paid assistantship or have campus job and get payslip biwekly. Just walk in and tell you are employed in Univ and they will get you enrolled for 15%"

Not verified.

Official link:

Employees of contracted T-Mobile Business Customers may request a corporate discount. The discount ranges from 0% to 15%, per Business Customer monthly volume. If available, the discount will appear on your monthly bill.*

Instructions:

1. Log in to My T-Mobile
2. Click on “Download the Form” and save the form on your computer
3. Complete your corporate discount request form
4. E-mail a copy of the form to our Business Care team

应该可以吧