Did you get a W-2? If yes, how much was the total?
For college students on work study, it's entirely possible no taxes were withheld because college students who work on campus (which is what work study is), no FICA/MC is withheld.
For 2017, if this is your only income and it was less than $6300, no return is due.
For 2017, if this was your only income and you made more, you have to file and yes, you include all income.
For 2017, if you had some unearned income, the issue is how much (see the back of the 1040EZ).