Sonoma Valley High School and Creekside High School, which share a campus, went into lockdown after an email was sent claiming one of the students had a weapon.
Deputies say after an extensive search of the Sonoma Valley High School campus, they determined the school threat was unfounded.
Nearby Adele Harrison Middle School and Prestwood Elementary School also went into lockdown out of "an abundance of caution" due to their proximity to the two high schools.
The previous request to avoid the schools has now been canceled.