From 2003 to 2007, the school had a student enrollment that fluctuated slightly above or below 1,500, with a 2003 enrollment of 1,516 and a 2007 enrollment of 1,449. Its average class size in 2003 was 17.4 students, compared to a state average of 19.2, while its 2007 class size was 20.7, compared to a state average of 18.8. Its 2003 student-faculty ratio was 10.4, compared to a state average of 11.5, while its 2007 student-faculty ratio was 12.4, compared to a state average of 11.0. On City-Data, which score schools from 0 (worst) to 100 (best), Emerson High School was given a score of 12, based on 2010 test scores. This compares with a citywide score of 10, a county score of 21 and a state score of 55. The school's 2007 graduation rate was 86.1 percent, compared to a state average of 87.9.