(A) No person shall drive a motor vehicle at a speed in excess of twenty (20) miles per hour while passing a school zone or while traveling upon any public thoroughfare on or across which children pass along to and from school during school days when schoolchildren are present.
(B) This section shall not be applicable unless appropriate signs are posted upon streets and highways under their respective jurisdiction and maintained by the city wherein the school zone is located. Such signs shall give proper due warning that a school zone is being approached and shall indicate the school zone and the maximum speed limit in effect during school days when schoolchildren are present. (1972 Code)