Chsd 155

Chsd 155 includes four high schools serving grades 9–12 in the same area, with 5,203 students combined. Across the nine 2025–2026 test comparisons, the schools’ average proficiency was above the state figure every time; area-wide mathematics was the relative weak spot, with the biggest school-to-school difference in grade 9 PreACT math. Two individual results were below the state: grade 9 PreACT math at Crystal Lake South and Crystal Lake Central.

Prairie Ridge has the broadest set of top results, leading five comparisons; its ACT English score was 72%, 22 percentage points above the state and 9 points above the other schools’ average. Cary-Grove stands out in math, leading grade 9 and 10 PreACT math at 54% and 49%. South leads grade 10 PreACT English and science, while Central was lowest in six of the nine comparisons. Results vary by subject and grade: South, for example, has both grade 10 strengths and the lowest ACT English and math scores.

Results shifted down overall: the four-school average fell in six of nine comparisons, and the average change was about −2 percentage points; grade 10 PreACT math fell 7 points, while grade 9 PreACT math rose 5. Central’s ACT results were an exception, rising 6 points in English, 6 in math and 7 in science. SchoolDigger ranks the district 116th of 738 in Illinois, at the 84th percentile with four stars; its school rankings moved down from 2023–2024 to 2025–2026 at three of the four schools. Context differs, too: 2024–2025 free/reduced lunch eligible figures ranged from 22% at Prairie Ridge to 35% at Central, and student-teacher ratios ranged from 16.3 to 17.6.