Yes, if you attended high school or college full time for five months or more of 2015, you would be considered a student for tax purposes.
Student defined. To qualify as a student, your child must be, during some part of each of any 5 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 5 calendar months do not have to be consecutive.
More information: https://www.irs.gov/publications/p17/ch03.html
