School Crossing Guard School Crossing Guards are an integral part of the Colleyville Police Department School Safety Program. Crossing guards provide the children that walk to and from school with safe access at high traffic areas near schools. Use of crossing guards affords the police department the ability to maintain available officers to respond to emergency and in-progress calls for service. Typical work schedule includes one hour in the morning and one hour in the afternoon. Relief positions will be on call if Regular crossing guards are absent. Minimum Qualifications: Must be 18 years of age or older.