Enrollment
669
Virginia · 2024-25 NCES data
Other / mixed grade configuration · Dumfries, VA
Mary Williams Elementary
Federal NCES profile for Mary Williams Elementary, including enrollment, faculty, free-lunch eligibility, demographics, and resource indicators - Resource Investment Index 52/100.
2024-25 NCES dataOther / mixed grade configurationNCES 510313002455
👥 S:T ratio 40
🌟 Gifted program 70
🎓 Counselors 33
📋 Attendance 63
Scored 0–100 from federal NCES and CRDC indicators, resource allocation, not test scores. Full methodology →
The verdict
Mary Williams Elementary earns 52/100 on the Resource Investment Index, with class sizes near the Virginia median. It is also more racially and ethnically mixed than most Virginia schools.
- #2 of 7
- schools in Dumfries · Resource Index
- 52
- Resource Index · Higher
- 14.9:1
- students per teacher
- 48.3%
- free-lunch eligible
Mary Williams Elementary has class sizes near the Virginia median. Computed live against every Virginia school reporting to NCES.
By Resource Investment Index, Mary Williams Elementary ranks #2 of 7 schools in Dumfries, VA.
School address
District: Prince William County Public Schools · Virginia
NCES ID 510313002455 Verify on NCES CCD record →
Teachers (FTE)
45.0
Federal CCD staff survey
Students per teacher
14.9:1
vs 13.9:1 Virginia avg
+7% vs state
Free-lunch eligible
48.3%
vs 57.6% Virginia avg
-16% vs state
Student-teacher ratio in context
How Mary Williams Elementary compares with Virginia and U.S. medians
What stands out at Mary Williams Elementary
Mary Williams Elementary is a mid-sized combined-grade school in Dumfries, Virginia, enrolling 669 students.
Class loads run somewhat heavier than typical: 14.9:1 puts it in the larger third of Virginia schools by student-teacher ratio.
Its free-meal eligibility rate of 48.3% lands close to the Virginia typical range, neither a high- nor low-need campus by this measure.
Enrollment of 669 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.
Against 195 statewide peers matched on enrollment and economic need, it ranks in the upper tier at #71.
Its student body is led by African American (34%) and Hispanic or Latino (28%), more mixed than most schools in the state (diversity index 75/100).
Counselor availability sits well past the ASCA benchmark, roughly 335 students sharing each counselor, though short of the most stretched campuses.
14.8% of students were chronically absent in the 2021-22 collection, in line with the post-pandemic national range.
Among Dumfries's public schools, it stands alongside Covington-Harper Elementary (1,025 students): Mary Williams Elementary is smaller than that campus by headcount and runs leaner classes (14.9:1 vs 17.7:1).
Prince William County Public Schools also operates Charles J. Colgan Sr. High (2,956 students) and Woodbridge High (2,898 students) alongside Mary Williams 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 Mary Williams Elementary compares
Mary Williams 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 | 14.9:1 | ▲ 7% | 13.9:1 | 15.7:1 |
| Free-lunch eligible | 48.3% | ▼ 16% | 57.6% | 51.7% |
| Enrollment | 669 | top 35% | - | - |
Source: NCES Common Core of Data School-level CCD + state/national means from Public School Universe · 2024-25
14.9:1
Leaner classes than 48% of US schools, a middle-of-the-pack class size.
669
Bigger than 78% of US schools by enrollment, mid-sized for the country.
Equity indicators (what these measure)
Economic need
48.3%
free-lunch eligible
- 16% below the Virginia average of 57.6%
Above the 40% Title I schoolwide threshold; federal funds support the whole school, not individual students.
Staffing depth
14.9:1
students per teacher
- 7% above state mean
Top 67% in Virginia - lower ratio than 33% of state schools
Close to the 15:1 benchmark most often cited for individualized attention.
Engagement
14.8%
chronically absent (missed 10%+ of school days)
In the 10-15% range, above the pre-pandemic national baseline but within the broader post-pandemic picture.
Funding equity
$13,913
per pupil, district-wide
- below Virginia avg of $14,649
Somewhat below the U.S. average per-pupil spend; funding constraints may affect programs, facilities, and staffing.
Support staff
Counselors2.0 FTE
Per 335 students, the combined health-and-guidance staffing load for this school.
Discipline context
4
in-school suspensions + 2 out-of-school
Suspension rate: 0.6 per 100 students. Combined in-school and out-of-school rate: 0.9 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
African American 34.4%
Hispanic or Latino 27.8%
Asian 17.3%
White 14.6%
Two or More 5.4%
American Indian / Alaska Native 0.3%
Native Hawaiian / Pacific Islander 0.1%
Largest group: African American at 34.4% of enrollment.
Student-body diversity index 75.0/100
Simpson diversity index - at 75.0, Mary Williams Elementary is more mixed than the Virginia school average of 53.7.
Programs
Gifted & talented Yes
Funding & spending
District-wide per-pupil expenditure for Prince William County Public Schools, which includes Mary Williams Elementary.
$13,913
Per student
-5%
vs Virginia
Avg $14,649
-16%
vs U.S.
Avg $16,593
Revenue mix
Local 47.2%
State 44.1%
Federal 8.6%
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 Mary Williams Elementary Compares to District-Mates
| School | Enrollment | Economic Profile | Student-Teacher Ratio |
|---|---|---|---|
| Charles J. Colgan Sr. High | Larger | Lower economic need | Higher S:T ratio |
| Woodbridge High | Larger | Similar economic need | Higher S:T ratio |
| Osbourn Park High | Larger | Similar economic need | Higher S:T ratio |
| Gainesville High | Larger | Lower economic need | Higher S:T ratio |
| Gar-Field High | Larger | Higher economic need | Higher S:T ratio |
Comparisons are relative to Mary Williams Elementary's own figures; each column derives from NCES Common Core of Data.
Other Schools in This District
- Enrollment
- 2,956
- Students per teacher
- 18.5:1
- Resource Index
- 41/100
- Enrollment
- 2,898
- Students per teacher
- 17.5:1
- Resource Index
- 38/100
- Enrollment
- 2,661
- Students per teacher
- 16.6:1
- Resource Index
- 42/100
- Enrollment
- 2,648
- Students per teacher
- 20.9:1
- Resource Index
- 41/100
- Enrollment
- 2,524
- Students per teacher
- 16.7:1
- Resource Index
- 49/100
Similar other schools in Dumfries
6 comparable other schools (grades Mixed) serving the same city.
Covington-Harper Elementary
Standard public school
1,025 students 17.7:1 students per teacher
John F. Pattie Sr. Elementary
Standard public school
906 students 12.9:1 students per teacher
A. Henderson Elementary
Standard public school
815 students 18.1:1 students per teacher
Swans Creek Elementary
Standard public school
619 students 16.3:1 students per teacher
Montclair Elementary
Standard public school
588 students 15.1:1 students per teacher
Dumfries Elementary
Standard public school
441 students 13:1 students per teacher
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 (~669 students)
Similar student-teacher ratio (~14.9:1)
Next steps
Verify locally before acting on Mary Williams Elementary's federal record.
- Compare Mary Williams Elementary against another school. Compare schools
- Prince William 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 Mary Williams Elementary
How many students attend Mary Williams Elementary?
Mary Williams Elementary has 669 students enrolled. It is a public school in Dumfries, VA.
What is the student-teacher ratio at Mary Williams Elementary?
The student-teacher ratio at Mary Williams Elementary is 14.9:1, which is 7% higher than the Virginia average of 13.9:1 and 5% lower than the national average of 15.7:1.
What percentage of students receive free lunch at Mary Williams Elementary?
48.3% of students at Mary Williams Elementary are eligible for free lunch, compared to the Virginia average of 57.6%.
What is the racial and ethnic makeup of Mary Williams Elementary?
The largest demographic group at Mary Williams Elementary is African American at 34.4% of enrollment, in Dumfries, VA. Its student body is more racially and ethnically mixed than most US schools, with a diversity index of 75.0/100.
What is the Resource Investment Index for Mary Williams Elementary?
Mary Williams Elementary has a Resource Investment Index of 52/100 (higher 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 Mary Williams Elementary rank among schools in Dumfries?
By Resource Investment Index, Mary Williams Elementary ranks #2 of 7 schools in Dumfries, VA. This compares federal resource and staffing data among local peers; it is not a test-score or academic ranking. See all schools in Dumfries on the city page.
Is Mary Williams Elementary a good school?
Mary Williams Elementary earns 52/100 on the Resource Investment Index, with class sizes near the Virginia median. It is also more racially and ethnically mixed than most 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 Prince William County Public Schools?
Besides Mary Williams Elementary, Prince William County Public Schools also operates Charles J. Colgan Sr. High (2,956 students), Woodbridge High (2,898 students), and Osbourn Park High (2,661 students). See the Prince William 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.