Police say an 18-year-old man is facing charges for trespassing at Watertown High School.
They say Davon Alvarez of Waterbury walked in behind students who had buzzed in to the high school but did not check in with anyone.
A teacher did not recognize Alvarez as a student and called police.
Police say he wasn't carrying anything suspicious or dangerous and was "curious about what different schools were like."
They say Alvarez did the same thing in a neighboring community last year.