The top reported proficiency rate is 37% in Math. The lowest is 26% in Science.
Original Research by School Decision on Illini Central Grade School
Illini Central Grade School serves kindergarten through fifth grade students in Mason City, a small farm town in Mason County in central Illinois. The school is part of a unified pre-K through 12 campus operated by Illini Central CUSD 189, which serves Mason City, Easton, and San Jose together on a single shared facility.
The enrollment is small, with a combined kindergarten through fifth grade population typical for a rural district of this size. The student body is predominantly white, with a small representation of Hispanic students and students of two or more races; Asian, Black, and Native American enrollments are minimal. Data on free-or-reduced-price lunch eligibility and special education or English learner populations were not available.
State test results from the most recent year show academic performance that warrants attention. In third and fourth grade mathematics, proficiency rates fall below what the field typically sees as adequate, and fourth grade English language arts results are particularly low. Fifth grade proficiency rates drop sharply in both math and English language arts compared to the earlier grades. Fifth grade science proficiency is similarly low. The school participates fully in state assessments, so the results reflect actual student performance in the tested cohorts rather than incomplete testing. A parent may want to look into current curriculum supports and intervention strategies during a school visit, to understand how the school is addressing this pattern.
Mason City itself is a residential, settled community of modest size built on older pre-WWII housing stock, where most residents own their homes. The town sits at the junction of Illinois Route 10 and Route 29 and has a compact, walkable footprint around a small downtown commercial core. Population has declined gradually over recent decades. The local economy centers on agriculture and farm-service businesses; the major confirmed in-town employer is an agricultural equipment dealer. The Mason City Public Library, located on the main street downtown, adjusts its hours when school is in session, and the unified Illini Central campus serves as a shared civic anchor for all three communities.
Recent district developments include a multi-year building addition and renovation project at the Mason City campus that was completed in summer 2025, adding modernized space including a senior "Reimagine Building" designed for capstone and career-readiness work. The district also adopted a new Strategic Plan for 2024–2030. These investments signal the district's commitment to sustained facility and program development despite the small, declining population base.
Housing values in the 62664 zip code are below state and national benchmarks, and affordability is strong relative to national standards. The median home value reflects the modest economic base and older housing stock, which may appeal to families seeking low housing costs but who should factor in the condition and age of most properties when evaluating a move.
Among the three districts in Mason County, Illini Central Grade School's proficiency index places it in the bottom quartile, well below the median and at or below the lowest performers. The school's grade band means it does not report high school graduation rates or advanced course access that would apply at the secondary level.
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