Summary:
The three schools in ZIP code 57564—Onida Elementary (K–5), Sully Buttes Middle (6–8), and Sully Buttes High (9–12)—serve 216 students in the Agar-Blunt-Onida School District 58-3. The clearest academic standout is Sully Buttes Middle: in 2025–2026, its all-grades proficiency was 14 percentage points above the state in ELA and 17 points above in math.
Sully Buttes Middle had the strongest comparable elementary and middle school results, with 63% proficiency in ELA and 61% in math, versus 49% and 44% statewide. Its results were above state levels in every reported grade for both subjects. At the other end, Onida Elementary was near state level in ELA at 49%, but its 37% math result was 7 points below state and 24 points below the middle school. Sully Buttes High had a mixed ACT profile: 18 points below state in ELA, 1 point above in math, and 5 points below in science; its graduation rate was 7 points above state, and its dropout rate was 2 points lower. SchoolDigger ranks the middle school 15th of 151 (90th percentile, five stars), the elementary school 129th of 203 (36th percentile, two stars), and the high school 97th of 130 (25th percentile, one star).
All-grades scores declined from the prior year at both the elementary and middle schools: about 4 points in ELA and 3 in math at Onida Elementary, and 5 in ELA and 3 in math at Sully Buttes Middle. Even so, the equal-school average advantage over state narrowed by 2 points in ELA and 4 in math. For context, the schools’ 2024–2025 student-teacher ratios ranged from 6.8 to 9.5; free/reduced lunch eligible shares for sy 2024–2025 ranged from 17% at the high school to 29% at the middle school, a descriptive difference that does not explain test results. The high school’s prior-year Smarter Balanced scores are not directly comparable with its latest ACT results.
Thank you for your feedback!