Enrollment
874
Virginia · 2024-25 NCES data
Other / mixed grade configuration · Clifton, VA
Union Mill Elementary
Federal NCES profile for Union Mill Elementary, including enrollment, faculty, free-lunch eligibility, demographics, and resource indicators - Resource Investment Index 48/100.
2024-25 NCES dataOther / mixed grade configurationNCES 510126002060
👥 S:T ratio 33
🌟 Gifted program 70
🎓 Counselors 13
📋 Attendance 78
Scored 0–100 from federal NCES and CRDC indicators, resource allocation, not test scores. Full methodology →
The verdict
Union Mill Elementary earns 48/100 on the Resource Investment Index, with class sizes larger than 89% of Virginia schools.
- #2 of 3
- public schools in Clifton · Resource Index
- 48
- Resource Index · Typical
- 16.8:1
- large classes for Virginia
- 10.4%
- free-lunch eligible
Union Mill Elementary has class sizes larger than 89% of Virginia schools. Computed live against every Virginia school reporting to NCES.
By Resource Investment Index, Union Mill Elementary ranks #2 of 3 public schools in Clifton, VA.
School address
District: Fairfax County Public Schools · Virginia
NCES ID 510126002060 Verify on NCES CCD record →
Teachers (FTE)
52.0
Federal CCD staff survey
Students per teacher
16.8:1
vs 13.9:1 Virginia avg
+21% vs state
Free-lunch eligible
10.4%
vs 57.6% Virginia avg
-82% vs state
Student-teacher ratio in context
How Union Mill Elementary compares with Virginia and U.S. medians
What stands out at Union Mill Elementary
Union Mill Elementary is a lower-poverty, mid-sized combined-grade school in Clifton, Virginia, enrolling 874 students.
Class loads run heavy: 16.8:1 is larger than about 89% of Virginia schools and 21% above the 13.9:1 state mean, so each teacher carries more students than is typical.
Comparatively few students face economic hardship here, 10.4% free-meal eligibility runs 82% below the Virginia average.
Enrollment of 874 puts it in the larger third of Virginia schools by headcount.
Its Resource Investment Index sits near the middle of the pack among 1,868 scored Virginia schools.
Among 195 similarly sized, similarly resourced-need Virginia schools statewide, it ranks #165, in the lower tier once campus size and economic need are matched.
Its student body is led by White (59%) and Asian (16%) (diversity index 60/100).
Counselor access is stretched at roughly 437 students per counselor, well above the ASCA-recommended 250:1 ceiling.
Attendance holds up well here: only 9.0% of students were chronically absent, below the typical post-pandemic national figure.
The surrounding Fairfax County Public Schools spends $17,977 per pupil, 23% above the Virginia average, a better-resourced district than most.
Fairfax County Public Schools also operates Lake Braddock Secondary (4,411 students) and Robinson Secondary (3,710 students) alongside Union Mill Elementary.
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 Union Mill Elementary compares
Union Mill Elementary on the metrics families compare, against Virginia and U.S. means.
| Metric | This school | vs Virginia | Virginia avg | U.S. avg |
|---|---|---|---|---|
| Students per teacher | 16.8:1 | ▲ 21% | 13.9:1 | 15.7:1 |
| Free-lunch eligible | 10.4% | ▼ 82% | 57.6% | 51.7% |
| Enrollment | 874 | top 19% | - | - |
Source: NCES Common Core of Data School-level CCD + state/national means from Public School Universe · 2024-25
16.8:1
Leaner classes than 32% of US schools, heavier class loads than most.
874
Bigger than 88% of US schools by enrollment, a large campus nationally.
Equity indicators (what these measure)
Economic need
10.4%
free-lunch eligible
- 82% below the Virginia average of 57.6%
Below the 40% Title I threshold, among the lower-need profiles in the state; federal aid targets individual qualifying students rather than schoolwide programs.
Staffing depth
16.8:1
students per teacher
- 21% above state mean
Top 89% in Virginia - lower ratio than 11% of state schools
Between 16:1 and 20:1, squarely in the typical U.S. public-school staffing range.
Engagement
9.0%
chronically absent (missed 10%+ of school days)
In the 5-10% range, close to the pre-pandemic national baseline.
Funding equity
$17,977
per pupil, district-wide
- above Virginia avg of $14,649
Somewhat above the U.S. public-school average, reflecting higher local or state investment per enrolled student.
Support staff
Counselors2.0 FTE
Per 437 students, the combined health-and-guidance staffing load for this school.
Discipline context
6
in-school suspensions + 6 out-of-school
Suspension rate: 0.7 per 100 students. Combined in-school and out-of-school rate: 1.4 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 59.4%
Asian 16.2%
Hispanic or Latino 10.6%
Two or More 8.8%
African American 4.8%
Native Hawaiian / Pacific Islander 0.1%
Largest group: White at 59.4% of enrollment.
Student-body diversity index 60.0/100
Simpson diversity index - at 60.0, Union Mill Elementary is more mixed than the Virginia school average of 53.7.
Programs
Gifted & talented Yes
Funding & spending
District-wide per-pupil expenditure for Fairfax County Public Schools, which includes Union Mill Elementary.
$17,977
Per student
+23%
vs Virginia
Avg $14,649
+8%
vs U.S.
Avg $16,593
Revenue mix
Local 66.6%
State 23.3%
Federal 10.1%
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 Union Mill Elementary Compares to District-Mates
| School | Enrollment | Economic Profile | Student-Teacher Ratio |
|---|---|---|---|
| Lake Braddock Secondary | Larger | Similar economic need | Similar S:T ratio |
| Robinson Secondary | Larger | Similar economic need | Similar S:T ratio |
| Hayfield Secondary | Larger | Higher economic need | Similar S:T ratio |
| Chantilly High | Larger | Similar economic need | Similar S:T ratio |
| West Springfield High | Larger | Similar economic need | Higher S:T ratio |
Comparisons are relative to Union Mill Elementary's own figures; each column derives from NCES Common Core of Data.
Other Schools in This District
- Enrollment
- 4,411
- Students per teacher
- 17:1
- Resource Index
- 57/100
- Enrollment
- 3,710
- Students per teacher
- 17.1:1
- Resource Index
- 54/100
- Enrollment
- 3,256
- Students per teacher
- 17.3:1
- Resource Index
- 53/100
- Enrollment
- 2,937
- Students per teacher
- 16.2:1
- Resource Index
- 47/100
- Enrollment
- 2,799
- Students per teacher
- 18.5:1
- Resource Index
- 45/100
Similar other schools statewide
Matched by enrollment size and by staffing ratio across all of Virginia, not just this city - a different peer set than the local comparisons above.
Similar enrollment (~874 students)
Next steps
Verify locally before acting on Union Mill Elementary's federal record.
- Compare Union Mill Elementary against another school. Compare schools
- Fairfax County Public Schools'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 Union Mill Elementary
How many students attend Union Mill Elementary?
Union Mill Elementary has 874 students enrolled. It is a public school in Clifton, VA.
What is the student-teacher ratio at Union Mill Elementary?
The student-teacher ratio at Union Mill Elementary is 16.8:1, which is 21% higher than the Virginia average of 13.9:1 and 7% higher than the national average of 15.7:1.
What percentage of students receive free lunch at Union Mill Elementary?
10.4% of students at Union Mill Elementary are eligible for free lunch, compared to the Virginia average of 57.6%.
What is the racial and ethnic makeup of Union Mill Elementary?
The largest demographic group at Union Mill Elementary is White at 59.4% of enrollment, in Clifton, VA. Its student body is more racially and ethnically mixed than most US schools, with a diversity index of 60.0/100.
What is the Resource Investment Index for Union Mill Elementary?
Union Mill Elementary has a Resource Investment Index of 48/100 (typical 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 Union Mill Elementary rank among public schools in Clifton?
By Resource Investment Index, Union Mill Elementary ranks #2 of 3 public schools in Clifton, VA. This compares federal resource and staffing data among local peers; it is not a test-score or academic ranking. See all public schools in Clifton on the city page.
Is Union Mill Elementary a good school?
Union Mill Elementary earns 48/100 on the Resource Investment Index, with class sizes larger than 89% of Virginia schools. 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 Fairfax County Public Schools?
Besides Union Mill Elementary, Fairfax County Public Schools also operates Lake Braddock Secondary (4,411 students), Robinson Secondary (3,710 students), and Hayfield Secondary (3,256 students). See the Fairfax County Public Schools 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.