crossing guard

crossing guard
    n 1: someone who helps people (especially children) at a traffic
         crossing
    

crossing guard \cross"ing guard`\, n.
   a person who stands at a street crossing to assist children
   to cross the street safely; -- usually used near schools
   during the times that children are entering or leaving the
   school.

   Note: Crossing guards may be employed by a municipality as
         auxiliary police officers, or may be unpaid volunteers.
         Some wear uniforms, others do not. They are commonly
         older citizens who are retired or not employed
         full-time at other tasks. At some schools, older
         students from the school are trained to perform the
         function of crossing guards.
         [PJC]