Tray Turner was hospitalized in St. Louis after falling from a staircase at the high school Monday.
The Collinsville Community Unit School District #10 is deeply saddened by his loss.
"Each student is special and Tray will be missed. We extend our heartfelt sympathy to his family and friends," the school released in a statement.
Thursday's homecoming parade has been cancelled. The homecoming football game, dance and coronation will go on as planned. "KAHOKstrong continues its efforts to support Tray’s family."
H.A.R.T., the district’s Help and Response Team of specially trained staff, is helping students and faculty deal with this tragic loss.
The school district asked the police department to conduct the investigation when it became clear the student had severe injuries. The accident happened as some 500 of the nearly 2,000 students at the school were heading to their lunch period.
Turner reportedly fell over a banister from the second floor. Two students, who were nearby, raced for help from teachers.
He was airlifted by ARCH helicopter from the school's football field.