According to the IRS, a full-time student is defined as a student who is enrolled for the number of hours or courses that the school considers to be full-time attendance. Keep in mind that each school defines "full time" in its own way (usually in terms of the number of courses or hours).
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.
Note: The five calendar months do not have to be consecutive.
More detailed information can be found in the Chapter "Personal Exemptions and Dependents" of Publication 17, Your Federal Income Tax.