Enrollment
1,585
California · 2024-25 NCES data
High school (grades 9-12) · San Mateo, CA
Hillsdale High
Federal NCES profile for Hillsdale High, including enrollment, faculty, free-lunch eligibility, demographics, and resource indicators - Resource Investment Index 48/100.
2024-25 NCES dataHigh school (grades 9-12)NCES 063498005923
👥 S:T ratio 31
📚 AP courses 85
🌟 Gifted program 30
🎓 Counselors 17
📋 Attendance 76
Scored 0–100 from federal NCES and CRDC indicators, resource allocation, not test scores. Full methodology →
The verdict
Hillsdale High earns 48/100 on the Resource Investment Index, with class sizes smaller than 83% of California schools. It is also more racially and ethnically mixed than most California schools.
- #1 of 3
- high schools in San Mateo · Resource Index
- 48
- Resource Index · Typical
- 17.2:1
- small classes for California
- 16.8%
- free-lunch eligible
Hillsdale High has class sizes smaller than 83% of California schools. Computed live against every California school reporting to NCES.
By Resource Investment Index, Hillsdale High ranks #1 of 3 high schools in San Mateo, CA.
School address
District: San Mateo Union High · California
NCES ID 063498005923 Verify on NCES CCD record →
Teachers (FTE)
92.0
Federal CCD staff survey
Students per teacher
17.2:1
vs 21.5:1 California avg
-20% vs state
Free-lunch eligible
16.8%
vs 55.5% California avg
-70% vs state
Student-teacher ratio in context
How Hillsdale High compares with California and U.S. medians
What stands out at Hillsdale High
Hillsdale High is a lower-poverty, large high school in San Mateo, California, enrolling 1,585 students.
Class sizes run a bit leaner than typical: 17.2:1 puts it in the smaller third of California schools by student-teacher ratio.
Comparatively few students face economic hardship here, 16.8% free-meal eligibility runs 70% below the California average.
By headcount it is one of the larger campuses in California, bigger than 94% of state schools at 1,585 students.
Its Resource Investment Index lands in the upper third of 9,998 scored California schools.
Against 307 statewide peers matched on enrollment and economic need, it ranks in the upper tier at #99.
Its student body is led by Hispanic or Latino (38%) and White (31%), more mixed than most schools in the state (diversity index 71/100).
On the academic-pipeline side it reports 17 Advanced Placement courses.
Counselor access is stretched at roughly 417 students per counselor, well above the ASCA-recommended 250:1 ceiling.
Attendance holds up well here: only 9.7% of students were chronically absent, below the typical post-pandemic national figure.
The surrounding San Mateo Union High spends $22,262 per pupil, 35% above the California average, a better-resourced district than most.
Among San Mateo's high schools, it stands alongside Aragon High (1,658 students): Hillsdale High is smaller than that campus by headcount and runs leaner classes (17.2:1 vs 22.1:1).
San Mateo Union High also operates Aragon High (1,658 students) and Burlingame High (1,583 students) alongside Hillsdale High.
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 Hillsdale High compares
Hillsdale High on the metrics families compare, against California and U.S. means.
| Metric | This school | vs California | California avg | U.S. avg |
|---|---|---|---|---|
| Students per teacher | 17.2:1 | ▼ 20% | 21.5:1 | 15.7:1 |
| Free-lunch eligible | 16.8% | ▼ 70% | 55.5% | 51.7% |
| Enrollment | 1,585 | top 6% | - | - |
Source: NCES Common Core of Data School-level CCD + state/national means from Public School Universe · 2024-25
17.2:1
Leaner classes than 29% of US schools, heavier class loads than most.
1,585
Bigger than 97% of US schools by enrollment, a large campus nationally.
Equity indicators (what these measure)
Economic need
16.8%
free-lunch eligible
- 70% below the California average of 55.5%
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
17.2:1
students per teacher
- 20% below state mean
Top 17% in California - lower ratio than 83% of state schools
Between 16:1 and 20:1, squarely in the typical U.S. public-school staffing range.
Engagement
9.7%
chronically absent (missed 10%+ of school days)
In the 5-10% range, close to the pre-pandemic national baseline.
Funding equity
$22,262
per pupil, district-wide
- above California avg of $16,509
Well above the U.S. public-school average, reflecting substantially higher local or state investment per enrolled student.
Support staff
Counselors3.8 FTE
Per 417 students, the combined health-and-guidance staffing load for this school.
Discipline context
9
in-school suspensions + 44 out-of-school
Suspension rate: 0.6 per 100 students. Combined in-school and out-of-school rate: 3.3 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
Hispanic or Latino 37.8%
White 30.9%
Asian 19.8%
Two or More 9.4%
African American 1.0%
Native Hawaiian / Pacific Islander 1.0%
American Indian / Alaska Native 0.1%
Largest group: Hispanic or Latino at 37.8% of enrollment.
Student-body diversity index 71.3/100
Simpson diversity index - at 71.3, Hillsdale High is more mixed than the California school average of 46.0.
Programs
AP courses offered 17
Funding & spending
District-wide per-pupil expenditure for San Mateo Union High, which includes Hillsdale High.
$22,262
Per student
+35%
vs California
Avg $16,509
+34%
vs U.S.
Avg $16,593
Revenue mix
Local 85.1%
State 11.5%
Federal 3.4%
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 Hillsdale High Compares to District-Mates
| School | Enrollment | Economic Profile | Student-Teacher Ratio |
|---|---|---|---|
| Aragon High | Similar size | Similar economic need | Higher S:T ratio |
| Burlingame High | Similar size | Similar economic need | Higher S:T ratio |
| San Mateo High | Similar size | Similar economic need | Similar S:T ratio |
| Mills High | Smaller | Similar economic need | Higher S:T ratio |
| Capuchino High | Smaller | Similar economic need | Similar S:T ratio |
Comparisons are relative to Hillsdale High's own figures; each column derives from NCES Common Core of Data.
Other Schools in This District
- Enrollment
- 1,658
- Students per teacher
- 22.1:1
- Resource Index
- 33/100
- Enrollment
- 1,583
- Students per teacher
- 22:1
- Resource Index
- 36/100
- Enrollment
- 1,557
- Students per teacher
- 18.5:1
- Resource Index
- 30/100
- Enrollment
- 1,115
- Students per teacher
- 21:1
- Resource Index
- 38/100
- Enrollment
- 1,061
- Students per teacher
- 17.4:1
- Resource Index
- 33/100
Similar high schools in San Mateo
2 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 California, not just this city - a different peer set than the local comparisons above.
Similar enrollment (~1,585 students)
Next steps
Verify locally before acting on Hillsdale High's federal record.
- Compare Hillsdale High against another school. Compare schools
- San Mateo Union High'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 Hillsdale High
How many students attend Hillsdale High?
Hillsdale High has 1,585 students enrolled. It is a high school in San Mateo, CA.
What is the student-teacher ratio at Hillsdale High?
The student-teacher ratio at Hillsdale High is 17.2:1, which is 20% lower than the California average of 21.5:1 and 10% higher 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 Hillsdale High?
16.8% of students at Hillsdale High are eligible for free lunch, compared to the California average of 55.5%.
What is the racial and ethnic makeup of Hillsdale High?
The largest demographic group at Hillsdale High is Hispanic or Latino at 37.8% of enrollment, in San Mateo, CA. Its student body is more racially and ethnically mixed than most US schools, with a diversity index of 71.3/100.
What is the Resource Investment Index for Hillsdale High?
Hillsdale High has a Resource Investment Index of 48/100 (typical 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 Hillsdale High rank among high schools in San Mateo?
By Resource Investment Index, Hillsdale High ranks #1 of 3 high schools in San Mateo, CA. This compares federal resource and staffing data among local peers; it is not a test-score or academic ranking. See all high schools in San Mateo on the city page.
Is Hillsdale High a good school?
Hillsdale High earns 48/100 on the Resource Investment Index, with class sizes smaller than 83% of California schools. It is also more racially and ethnically mixed than most California 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 San Mateo Union High?
Besides Hillsdale High, San Mateo Union High also operates Aragon High (1,658 students), Burlingame High (1,583 students), and San Mateo High (1,557 students). See the San Mateo Union High 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.