It was around 10:00 a.m. when a security guard found a message scribbled on the wall of a bathroom at Souderton Area High School.
Students and staff were evacuated to the school's sports stadium, and were later sent home for the day.
Police say they didn't find anything in a two hour search of the school, but they're continuing their search for whoever left the note.
Classes will resume as normal on Tuesday.
