The average aide salary at Festus Elem. was $53,131 , which is 130 percent higher than the average salary for this job in Missouri, and 64 percent higher than the national average for this job . Aide salaries at Festus Elem. typically range from $47,850 to $63,575 (25th to 75th percentile). The highest reported aide salary was $70,700. There are 17 employees at Festus Elem. with the job title aide.