Enrollment
673
Connecticut · 2024-25 NCES data
High school (grades 9-12) · Wallingford, CT
Mark T. Sheehan High School
Federal NCES profile for Mark T. Sheehan High School, including enrollment, faculty, free-lunch eligibility, demographics, and resource indicators - Resource Investment Index 72/100.
2024-25 NCES dataHigh school (grades 9-12)NCES 090474000956
👥 S:T ratio 61
📚 AP courses 100
🌟 Gifted program 70
🎓 Counselors 66
📋 Attendance 61
Scored 0–100 from federal NCES and CRDC indicators, resource allocation, not test scores. Full methodology →
The verdict
Mark T. Sheehan High School earns 72/100 on the Resource Investment Index, with class sizes smaller than 82% of Connecticut schools.
- #1 of 11
- public schools in Wallingford · Resource Index
- 72
- Resource Index · Higher
- 9.8:1
- small classes for Connecticut
- 21.7%
- free-lunch eligible
Mark T. Sheehan High School has class sizes smaller than 82% of Connecticut schools. Computed live against every Connecticut school reporting to NCES.
By Resource Investment Index, Mark T. Sheehan High School ranks #1 of 11 public schools in Wallingford, CT.
School address
District: Wallingford School District · Connecticut
NCES ID 090474000956 Verify on NCES CCD record →
Teachers (FTE)
69.0
Federal CCD staff survey
Students per teacher
9.8:1
vs 12.1:1 Connecticut avg
-19% vs state
Free-lunch eligible
21.7%
vs 36.4% Connecticut avg
-40% vs state
Student-teacher ratio in context
How Mark T. Sheehan High School compares with Connecticut and U.S. medians
What stands out at Mark T. Sheehan High School
Mark T. Sheehan High School is a mid-sized high school in Wallingford, Connecticut, enrolling 673 students.
Class sizes run a bit leaner than typical: 9.8:1 puts it in the smaller third of Connecticut schools by student-teacher ratio.
Economic need runs somewhat below the state's typical profile, with 21.7% of students eligible for free meals.
Enrollment of 673 puts it in the larger third of Connecticut schools by headcount.
Its Resource Investment Index outscores 90% of the 1,003 Connecticut schools with a score on record, a top-tier result on this measure.
Among 198 similarly sized, similarly resourced-need Connecticut schools statewide, it ranks #21, a top-tier result once campus size and economic need are matched.
Its student body is led by White (65%) and Hispanic or Latino (22%) (diversity index 53/100).
On the academic-pipeline side it reports 24 Advanced Placement courses.
Counselor coverage is strong, about 168 students per counselor, inside the American School Counselor Association's recommended 250:1.
15.5% of students were chronically absent in the 2021-22 collection, in line with the post-pandemic national range.
The federal civil-rights collection also records 4 expulsions at this campus for 2021-22.
Among Wallingford's high schools, it stands alongside Lyman Hall High School (936 students): Mark T. Sheehan High School is smaller than that campus by headcount and runs leaner classes (9.8:1 vs 9.8:1).
Wallingford School District also operates Lyman Hall High School (936 students) and Dag Hammarskjold Middle School (593 students) alongside Mark T. Sheehan High 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 Mark T. Sheehan High School compares
Mark T. Sheehan High School on the metrics families compare, against Connecticut and U.S. means.
| Metric | This school | vs Connecticut | Connecticut avg | U.S. avg |
|---|---|---|---|---|
| Students per teacher | 9.8:1 | ▼ 19% | 12.1:1 | 15.7:1 |
| Free-lunch eligible | 21.7% | ▼ 40% | 36.4% | 51.7% |
| Enrollment | 673 | top 17% | - | - |
Source: NCES Common Core of Data School-level CCD + state/national means from Public School Universe · 2024-25
9.8:1
Leaner classes than 90% of US schools, among the more generously staffed nationally.
673
Bigger than 78% of US schools by enrollment, mid-sized for the country.
Equity indicators (what these measure)
Economic need
21.7%
free-lunch eligible
- 40% below the Connecticut average of 36.4%
Below the 40% Title I threshold; federal aid targets individual qualifying students rather than schoolwide programs.
Staffing depth
9.8:1
students per teacher
- 19% below state mean
Top 18% in Connecticut - lower ratio than 82% of state schools
Well under the widely cited 15:1 individualized-attention benchmark, among the leaner class loads nationally.
Engagement
15.5%
chronically absent (missed 10%+ of school days)
In the 15-20% range, nearing the "high" absenteeism threshold.
Funding equity
$24,840
per pupil, district-wide
- above Connecticut avg of $23,870
Well above the U.S. public-school average, reflecting substantially higher local or state investment per enrolled student.
Support staff
Counselors4.0 FTE
Per 168 students, the combined health-and-guidance staffing load for this school.
Discipline context
44
in-school suspensions + 31 out-of-school
Suspension rate: 6.5 per 100 students. Combined in-school and out-of-school rate: 11.1 per 100 students. Reported via the Civil Rights Data Collection. Includes 4 expulsions.
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 64.9%
Hispanic or Latino 21.5%
Asian 6.4%
Two or More 4.5%
African American 2.4%
American Indian / Alaska Native 0.1%
Native Hawaiian / Pacific Islander 0.1%
Largest group: White at 64.9% of enrollment.
Student-body diversity index 52.6/100
Simpson diversity index - at 52.6, Mark T. Sheehan High School is more mixed than the Connecticut school average of 50.5.
Programs
AP courses offered 24
Gifted & talented Yes
Funding & spending
District-wide per-pupil expenditure for Wallingford School District, which includes Mark T. Sheehan High School.
$24,840
Per student
+4%
vs Connecticut
Avg $23,870
+50%
vs U.S.
Avg $16,593
Revenue mix
Local 62.6%
State 30.8%
Federal 6.6%
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 Mark T. Sheehan High School Compares to District-Mates
| School | Enrollment | Economic Profile | Student-Teacher Ratio |
|---|---|---|---|
| Lyman Hall High School | Larger | Similar economic need | Similar S:T ratio |
| Dag Hammarskjold Middle School | Similar size | Similar economic need | Similar S:T ratio |
| James H. Moran Middle School | Similar size | Similar economic need | Similar S:T ratio |
| Cook Hill School | Smaller | Higher economic need | Higher S:T ratio |
| Moses Y. Beach School | Smaller | Similar economic need | Higher S:T ratio |
Comparisons are relative to Mark T. Sheehan High School's own figures; each column derives from NCES Common Core of Data.
Other Schools in This District
- Enrollment
- 936
- Students per teacher
- 9.8:1
- Resource Index
- 57/100
- Enrollment
- 593
- Students per teacher
- 10.2:1
- Resource Index
- 58/100
- Enrollment
- 531
- Students per teacher
- 8.8:1
- Resource Index
- 63/100
- Enrollment
- 357
- Students per teacher
- 11.5:1
- Resource Index
- 49/100
- Enrollment
- 326
- Students per teacher
- 12.1:1
- Resource Index
- 40/100
Similar high schools in Wallingford
1 comparable high schools (grades 9-12) serving the same city.
Similar high schools statewide
Matched by enrollment size and by staffing ratio across all of Connecticut, not just this city - a different peer set than the local comparisons above.
Similar enrollment (~673 students)
Next steps
Verify locally before acting on Mark T. Sheehan High School's federal record.
- Compare Mark T. Sheehan High School against another school. Compare schools
- Wallingford School District'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 Mark T. Sheehan High School
How many students attend Mark T. Sheehan High School?
Mark T. Sheehan High School has 673 students enrolled. It is a high school in Wallingford, CT.
What is the student-teacher ratio at Mark T. Sheehan High School?
The student-teacher ratio at Mark T. Sheehan High School is 9.8:1, which is 19% lower than the Connecticut average of 12.1:1 and 38% lower than the national average of 15.7:1. Lower ratios generally mean more individual attention per student.
What percentage of students receive free lunch at Mark T. Sheehan High School?
21.7% of students at Mark T. Sheehan High School are eligible for free lunch, compared to the Connecticut average of 36.4%.
What is the racial and ethnic makeup of Mark T. Sheehan High School?
The largest demographic group at Mark T. Sheehan High School is White at 64.9% of enrollment, in Wallingford, CT. Its student body is more racially and ethnically mixed than most US schools, with a diversity index of 52.6/100.
What is the Resource Investment Index for Mark T. Sheehan High School?
Mark T. Sheehan High School has a Resource Investment Index of 72/100 (higher reported resources relative to schools nationally) based on 5 factors: student-teacher ratio, AP course offerings, counselor availability, attendance rates. Not a test-score or academic measure (national median ~41/100, see methodology).
How does Mark T. Sheehan High School rank among public schools in Wallingford?
By Resource Investment Index, Mark T. Sheehan High School ranks #1 of 11 public schools in Wallingford, CT. This compares federal resource and staffing data among local peers; it is not a test-score or academic ranking. See all public schools in Wallingford on the city page.
Is Mark T. Sheehan High School a good school?
Mark T. Sheehan High School earns 72/100 on the Resource Investment Index, with class sizes smaller than 82% of Connecticut 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 Wallingford School District?
Besides Mark T. Sheehan High School, Wallingford School District also operates Lyman Hall High School (936 students), Dag Hammarskjold Middle School (593 students), and James H. Moran Middle School (531 students). See the Wallingford School District 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.