Enrollment
526
Illinois · 2024-25 NCES data
Elementary school (grades K-5) · Mendota, IL
Northbrook School
Federal NCES profile for Northbrook School, including enrollment, faculty, free-lunch eligibility, demographics, and resource indicators - Resource Investment Index 23/100.
2024-25 NCES dataElementary school (grades K-5)NCES 172562002773
👥 S:T ratio 42
🌟 Gifted program 30
🎓 Counselors 0
📋 Attendance 21
Scored 0–100 from federal NCES and CRDC indicators, resource allocation, not test scores. Full methodology →
The verdict
Northbrook School earns 23/100 on the Resource Investment Index, with class sizes near the Illinois median.
- #3 of 3
- elementary schools in Mendota · Resource Index
- 23
- Resource Index · Lower
- 14.6:1
- students per teacher
- 526
- students enrolled
Northbrook School has class sizes near the Illinois median. Computed live against every Illinois school reporting to NCES.
By Resource Investment Index, Northbrook School ranks #3 of 3 elementary schools in Mendota, IL.
School address
District: Mendota Ccsd 289 · Illinois
NCES ID 172562002773 Verify on NCES CCD record →
Teachers (FTE)
36.0
Federal CCD staff survey
Students per teacher
14.6:1
vs 14:1 Illinois avg
+4% vs state
Student-teacher ratio in context
How Northbrook School compares with Illinois and U.S. medians
What stands out at Northbrook School
Northbrook School is a mid-sized elementary school in Mendota, Illinois, enrolling 526 students.
Class loads run somewhat heavier than typical: 14.6:1 puts it in the larger third of Illinois schools by student-teacher ratio.
Enrollment of 526 puts it in the larger third of Illinois schools by headcount.
Its Resource Investment Index trails 92% of the 3,845 Illinois schools with a score on record, one of the lower results on this measure.
Its student body is led by White (54%) and Hispanic or Latino (40%) (diversity index 54/100).
Counselor access is stretched at roughly 526 students per counselor, well above the ASCA-recommended 250:1 ceiling.
Chronic absenteeism is elevated: 31.7% of students missed 10% or more of school days (2021-22 Civil Rights Data Collection).
The surrounding Mendota Ccsd 289 spends $13,069 per pupil, 23% below the Illinois average, a leaner-resourced district than most.
Among Mendota's elementary schools, it stands alongside Lincoln Elem School (319 students): Northbrook School is larger than that campus by headcount and runs heavier classes (14.6:1 vs 14.5:1).
Mendota Ccsd 289 also operates Lincoln Elem School (319 students) and Blackstone Elem School (197 students) alongside Northbrook School.
Sourced from NCES CCD, CRDC, and F-33 (federal records, not a quality verdict). How we source and compute this.
Source: National Center for Education Statistics Common Core of Data + CRDC + F-33 · 2024-25
How Northbrook School compares
Northbrook School on the metrics families compare, against Illinois and U.S. means.
| Metric | This school | vs Illinois | Illinois avg | U.S. avg |
|---|---|---|---|---|
| Students per teacher | 14.6:1 | ▲ 4% | 14:1 | 15.7:1 |
| Enrollment | 526 | top 27% | - | - |
Source: NCES Common Core of Data School-level CCD + state/national means from Public School Universe · 2024-25
14.6:1
Leaner classes than 51% of US schools, a middle-of-the-pack class size.
526
Bigger than 65% of US schools by enrollment, mid-sized for the country.
Equity indicators (what these measure)
Staffing depth
14.6:1
students per teacher
- 4% above state mean
Top 64% in Illinois - lower ratio than 36% of state schools
Close to the 15:1 benchmark most often cited for individualized attention.
Engagement
31.7%
chronically absent (missed 10%+ of school days)
At or above 20%, the commonly used threshold for "high" chronic absenteeism, signaling significant barriers to regular attendance.
Funding equity
$13,069
per pupil, district-wide
- below Illinois avg of $17,042
Well below the U.S. average per-pupil spend, a notably leaner funding position that may affect programs, facilities, and staffing.
Support staff
Counselors1.0 FTE
Per 526 students, the combined health-and-guidance staffing load for this school.
Discipline context
43
in-school suspensions + 27 out-of-school
Suspension rate: 8.2 per 100 students. Combined in-school and out-of-school rate: 13.3 per 100 students. Reported via the Civil Rights Data Collection.
Overview
- Common Core of Data (June 2026): enrollment, staffing, and the student-teacher ratio above.
- Civil Rights Data Collection: discipline counts and program access (AP, gifted, special education).
- F-33 School District Finance Survey: the district-wide per-pupil spending figures below.
Three separate federal collections, each on its own reporting cadence - which is why this school's numbers line up on a consistent basis against every other school and state on this site, rather than mixing figures pulled from different survey years.
Student demographics
White 54.2%
Hispanic or Latino 40.3%
Two or More 3.1%
African American 2.3%
American Indian / Alaska Native 0.2%
Largest group: White at 54.2% of enrollment.
Student-body diversity index 54.2/100
Simpson diversity index - at 54.2, Northbrook School is more mixed than the Illinois school average of 38.9.
Programs
Funding & spending
District-wide per-pupil expenditure for Mendota Ccsd 289, which includes Northbrook School.
$13,069
Per student
-23%
vs Illinois
Avg $17,042
-21%
vs U.S.
Avg $16,593
Revenue mix
Local 45.9%
State 39.8%
Federal 14.3%
Source: NCES F-33 School District Finance Survey District-level finance · FY 2021-22 Per-pupil expenditure reflects the district-wide average. Individual school budgets are not reported at the federal level.
How Northbrook School Compares to District-Mates
| School | Enrollment | Economic Profile | Student-Teacher Ratio |
|---|---|---|---|
| Lincoln Elem School | Smaller | No free-lunch data | Similar S:T ratio |
| Blackstone Elem School | Smaller | No free-lunch data | Lower S:T ratio |
Comparisons are relative to Northbrook School's own figures; each column derives from NCES Common Core of Data.
Other Schools in This District
- Enrollment
- 319
- Students per teacher
- 14.5:1
- Resource Index
- 24/100
- Enrollment
- 197
- Students per teacher
- 11.6:1
- Resource Index
- 28/100
Similar elementary schools in Mendota
2 comparable elementary schools (grades K-5) serving the same city.
Similar elementary schools statewide
Matched by enrollment size and by staffing ratio across all of Illinois, not just this city - a different peer set than the local comparisons above.
Similar enrollment (~526 students)
Similar student-teacher ratio (~14.6:1)
Next steps
Verify locally before acting on Northbrook School's federal record.
- Compare Northbrook School against another school. Compare schools
- Mendota Ccsd 289's spending and staffing shape this school. District profile
- Confirm current enrollment and boundaries with the school. Choosing guide
Federal record (CCD 2024-25, CRDC 2021-22) - PlainSchools assigns no subjective rating; the composite quality score is a transparent, reproducible index computed from this cited federal data.
Frequently asked questions about Northbrook School
How many students attend Northbrook School?
Northbrook School has 526 students enrolled. It is an elementary school in Mendota, IL.
What is the student-teacher ratio at Northbrook School?
The student-teacher ratio at Northbrook School is 14.6:1, which is 4% higher than the Illinois average of 14:1 and 7% lower than the national average of 15.7:1.
What is the racial and ethnic makeup of Northbrook School?
The largest demographic group at Northbrook School is White at 54.2% of enrollment, in Mendota, IL. Its student body is more racially and ethnically mixed than most US schools, with a diversity index of 54.2/100.
What is the Resource Investment Index for Northbrook School?
Northbrook School has a Resource Investment Index of 23/100 (lower reported resources relative to schools nationally) based on 4 factors: student-teacher ratio, counselor availability, attendance rates. Not a test-score or academic measure (national median ~41/100, see methodology).
How does Northbrook School rank among elementary schools in Mendota?
By Resource Investment Index, Northbrook School ranks #3 of 3 elementary schools in Mendota, IL. This compares federal resource and staffing data among local peers; it is not a test-score or academic ranking. See all elementary schools in Mendota on the city page.
Is Northbrook School a good school?
Northbrook School earns 23/100 on the Resource Investment Index, with class sizes near the Illinois median. This is a resource snapshot, not an academic rating; see the Resource Investment Index question above for what the number does and doesn't measure.
What other schools are in Mendota Ccsd 289?
Besides Northbrook School, Mendota Ccsd 289 also operates Lincoln Elem School (319 students) and Blackstone Elem School (197 students). See the Mendota Ccsd 289 district page for the complete list.
Related tools
Every figure on PlainSchools is rendered directly from the source NCES, CRDC and F-33 federal records, no number is typed in by an editor. Each school's figures reflect its most recent NCES/CRDC submission on file. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of June 2026.