The middle and high schools in Poynette closed Friday after a jar of formaldehyde broke in an agriculture classroom.
The high school was evacuated after 9 a.m. Friday. Two students in the class were treated at the scene. One of the students had a cut to his hand, according to school officials.
The middle school closed for the day because of shared bus routes with the high school.
Staff was allowed back in the school at 10:30 a.m., and the school is expected to open as scheduled on Monday.