No person upon roller skates, or riding in or by means of any coaster, toy vehicle, or similar device, shall go upon any roadway except while crossing a street on a crosswalk and when so crossing such person shall be granted all of the rights and shall be subject to all of the duties applicable to pedestrians. This section shall not apply upon any street while set aside as a play street as authorized by ordinance of the city. (Ord. 210 § 31, 1957)