Yes, this is possible if you entered the military during the year and were a full-time student before.
According to the IRS:
"A full-time student is a student who is enrolled for the number of hours or courses that the school considers to be full-time attendance.
To qualify as a student, the person must be, during some part of each of any five calendar months of the year:
- A full-time student at a school that has a regular teaching staff, course of study, and a regularly enrolled student body at the school, or
- A student taking a full-time, on-farm training course given by a school described in (1), or by a state, county, or local government agency.
The five calendar months do not have to be consecutive."