Old Saybrook Middle School was evacuated on Tuesday morning because of a non-specific threat, according to police, and nothing threatening was found during the search.
Police said the threat was written on a wall.
All students were brought from the middle school, located at 60 Sheffield St., to the high school, located at 1111 Boston Post Road. The students are continuing their school day at the high school and will have lunch there, according to police.
Parents are being told they can pick up their child if they feel the need to do so, but that students will be put on buses at their normal time for transportation home, police said.
Bomb experts were called to the middle school to investigate and determined that the school is clear.
The investigation continues and the school will be open after hours for people to pick up their belongings, according to police.