A firework has been let off near the grounds of Scalby School by a student.
The incident happened yesterday, with a text sent out to parents this afternoon briefly outlining the events.
A full investigation has been launched by the school to find out who was behind the incident.
The text to parents read: "at the end of school yesterday, a student discharged a firework in the vicinity of the school grounds. Please be assured that a full investigation has been launched today in order to identify who was responsible."