A motor vehicle owned or hired by a board of school directors shall not be operated in the transportation of school-children at any time when the owner and operator thereof is not insured under a liability policy issued by an insurance company authorized to transact business in this State to indemnify against liability for damages for personal injuries or damages to property. The amount of insurance shall be a minimum of $100,000.00 for injury to, or death of any one person in any accident, subject to a minimum limit per accident of $300,000.00 for injuries to or death of all persons in any one accident if the vehicle has a seating capacity of nine passengers or less. If the vehicle has a seating capacity in excess of nine passengers the amount of insurance shall be a minimum of $300,000.00 for injury to, or death of any one person in any accident, and subject to a minimum limit per accident of $500,000.00 for injuries to or death of all persons in any one accident. In addition, a minimum limit of $50,000.00 per occurrence for property damage shall be required. It shall be the duty of the school directors to require the filing, by or with them, of proof that the insurance is in force prior to the opening of each school year and that it is kept in force so long as school-children are being transported. A person who violates a provision of this section shall be fined not more than $500.00 or imprisoned not more than six months, or both. This section shall not apply to any person who transports only his or her own children, whether with or without compensation. (Amended 1965, No. 109, § 2; 1975, No. 149 (Adj. Sess.), § 2.)