The Illinois State Board of Education (ISBE) said 36.3 percent of Herrin High School's (HHS) 2015 senior class was "college ready."
The state average for college readiness in 2015 was 46 percent. Northside College Preparatory High School (98.1 percent) had the highest college readiness rate in the state. Robeson High School (zero percent) had the lowest.
All students who score a 21 on the ACT qualify as "college ready."
"(This score) shows that students have learned important academic skills that they will need in order to succeed in college and careers," ISBE wrote in its analysis. "While academic preparation is an essential part of readiness for college and careers, students also need persistence, motivation, time management, and technical skills."
HHS students did better on math (31.5 percent) and English (63 percent), and worse on science (26.7 percent) and reading (29.5 percent).
Only 13.7 percent of HHS students were college ready in all four subjects, according to ISBE.
The 2015 state average was 25 percent.
Among high schools in Williamson County, class of 2015 college readiness rates at Carterville High School (61.5 percent) and Marion High School (42.4 percent) were all higher than at HHS. Crab Orchard High School (28.9 percent) and Johnston City High School (29.9 percent) were all lower.
Enrollment at HHS in 2015 was 750; 199 students (26.53 percent) were freshmen; 162 (21.6 percent) were seniors.