The average teacher salary at Mercer High was $29,164 , which is 49 percent lower than the average salary for this job in Missouri, and 55 percent lower than the national average for this job . Teacher salaries at Mercer High typically range from $22,933 to $38,250 (25th to 75th percentile). The highest reported teacher salary was $45,000. There are 10 employees at Mercer High with the job title teacher.