Schools in Waterloo, IL

Waterloo, Illinois, has five schools serving prekindergarten through grade 12: three elementary schools, W J Zahnow Elementary School, Rogers Elementary School and Gardner Elementary School; Waterloo Junior High School; and Waterloo High School. Because schools serve different grades and tests, all-grades comparisons are not fully like-for-like; no test scores were supplied for Zahnow. Most importantly, every school with supplied test results scored above its matching state comparison.

Waterloo High School was above the state in all three grade 11 ACT subjects in 2025–2026, by 9 points in ELA, 10 in math and 10 in science. Waterloo Junior High School had the strongest all-grades ELA result among the schools with IAR results: 79%, 22 points above the state, though its 50% math result was 7 points below the district’s. Rogers Elementary School stood out in grade 3, beating the state by 23 points in ELA and 25 in math. Gardner Elementary School led in grade 5 science, 21 points above the state. Rogers also had the lowest chronic absenteeism, at 4%, compared with 5% at Gardner and 12% at the junior high and high school.

Results moved in different directions over time: junior high all-grades ELA and math each rose 4 points, while Rogers’ ELA fell 4 and math fell 6. At the high school, grade 11 ACT scores declined by 6 to 7 points across subjects, and its state advantages narrowed; grade 10 PreACT science, by contrast, rose 8 points. SchoolDigger percentiles also declined from 2023–2024 to 2025–2026 at the high school (89th to 83rd), junior high (90th to 80th) and Gardner (84th to 80th). The reported free/reduced lunch eligible shares were 18%–25% in 2024–2025; student-teacher ratios ranged from 14.7 at Zahnow to 17.1 at the high school.