745 ILCS 25/3
Within six months from the date that such injury was received or such cause of action accrued, any person who is about to commence any civil action in any court against any school district for damages on account of any injury to his person or property shall file in the office of the school board attorney, if there is a school board attorney, and also in the office of the clerk or secretary of the school board, either by himself, his agent or attorney, a statement in writing signed by himself, his agent or attorney, giving the name of the person to whom the cause of action has accrued, the name and residence of the person injured, the date and about the hour of the accident, the place or location where the accident occurred and the name and address of the attending physician, if any.
With respect to non-profit private schools the statement in writing required hereunder shall be filed in the office of the Superintendent or Principal of such school.
745 ILCS 25/3