Illini Central High School

As a rural-scale four-year high school in Mason City, Illinois, Illini Central High School instructs 172 students from grades 9 through 12, run under Illini Central CUSD 189. That puts it 79% leaner than the typical public school in Illinois, which averages around 834 students.

Illini Central High School is one of 4 schools operated by Illini Central CUSD 189, a district that educates 640 students overall.

Looking at the student body, Illini Central High School shows that nearly all students (96%) are White. The remainder looks like 2% multiracial. That composition is broadly in line with Mason County as a whole.

Looking at school resources, On paper, Illini Central High School has 21 full-time-equivalent teachers, translating to a class-load average of around 8.2:1. The state averages around 13.8:1, so this campus is tighter than the state norm typical. About 38% of enrolled students meet the income threshold for free or reduced-price lunch, which schools and policymakers use as a rough income-mix signal. By comparison, Mason County runs at roughly 51%, so the school's eligibility rate is meaningfully below the surrounding baseline.

After controlling for student poverty, Illini Central High School falls in the UNDERPERFORMING tier of the BeatsExpectations residual. Given its student profile, a typical campus would land near 49.4%; this one comes in at 26.1%, -23.2 points off the demographic line.

In the area at large, community-level numbers for Mason County indicate the typical household earns roughly $62,845 per year, 17% of adults hold a bachelor's degree or higher, and census figures put the poverty rate at about 11%. Across Mason County's 9 public schools (combined enrollment of about 2,124 students), Illini Central High School is one campus in the mix.

The closest other public school is Illini Central Middle School, roughly 0.0 miles away. Within five miles, there are 3 other public schools. Ranking that nearby cluster on reported proficiency puts Illini Central High School at 8th of 8; the average score across the group is 38.5%.

Geographically, the school is in an outlying area.

Five-year trend. Looking back 7 years, enrollment at Illini Central High School has fell 11%, going from 193 students in 2018 to 172 in 2025. The student-to-teacher ratio fell from 9.9:1 in 2018 to 8.2:1 today.

On allk12, recent activity here tends to focus on fundraisers, lost-and-found posts, and report-card season. Posting is open to anyone connected to the school.