Enrollment
34
California · 2024-25 NCES data
Elementary school (grades K-5) · Arcata, CA
Trillium Charter
Federal NCES profile for Trillium Charter, including enrollment, faculty, free-lunch eligibility, demographics, and resource indicators - Resource Investment Index 25/100.
2024-25 NCES dataElementary school (grades K-5)NCES 062943011947Charter school
👥 S:T ratio 32
🌟 Gifted program 30
📋 Attendance 12
Scored 0–100 from federal NCES and CRDC indicators, resource allocation, not test scores. Full methodology →
The verdict
Trillium Charter earns 25/100 on the Resource Investment Index, even as it posts class sizes smaller than 83% of California schools. It is also one of the smallest schools in California.
- #4 of 6
- elementary schools in Arcata · Resource Index
- 25
- Resource Index · Lower
- 17:1
- small classes for California
- 76.5%
- free-lunch eligible
Trillium Charter has class sizes smaller than 83% of California schools. Computed live against every California school reporting to NCES.
By Resource Investment Index, Trillium Charter ranks #4 of 6 elementary schools in Arcata, CA.
School address
District: Pacific Union Elementary · California
NCES ID 062943011947 Verify on NCES CCD record →
Teachers (FTE)
2.0
Federal CCD staff survey
Students per teacher
17:1
vs 21.5:1 California avg
-21% vs state
Free-lunch eligible
76.5%
vs 55.5% California avg
+38% vs state
Student-teacher ratio in context
How Trillium Charter compares with California and U.S. medians
What stands out at Trillium Charter
Trillium Charter is a high-poverty, small charter elementary school in Arcata, California, enrolling 34 students.
Class sizes run a bit leaner than typical: 17:1 puts it in the smaller third of California schools by student-teacher ratio.
Economic need runs somewhat above the state's typical profile, with 76.5% of students eligible for free meals.
This is a small campus: fewer students than 95% of California schools, with 34 enrolled.
Its Resource Investment Index lands in the lower third of 9,998 scored California schools.
Among 132 similarly sized, similarly resourced-need California schools statewide, it ranks #106, in the lower tier once campus size and economic need are matched.
Chronic absenteeism is elevated: 35.3% of students missed 10% or more of school days (2021-22 Civil Rights Data Collection).
The surrounding Pacific Union Elementary spends $10,212 per pupil, 38% below the California average, a leaner-resourced district than most.
Its district draws 17.7% of revenue from federal sources, an above-typical federal share that tends to track a higher-need student population.
Among Arcata's elementary schools, it stands alongside Pacific Union Elementary (534 students): Trillium Charter is smaller than that campus by headcount and runs leaner classes (17:1 vs 19.1:1).
Its district, Pacific Union Elementary, also runs Pacific Union Elementary (534 students).
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 Trillium Charter compares
Trillium Charter on the metrics families compare, against California and U.S. means.
| Metric | This school | vs California | California avg | U.S. avg |
|---|---|---|---|---|
| Students per teacher | 17:1 | ▼ 21% | 21.5:1 | 15.7:1 |
| Free-lunch eligible | 76.5% | ▲ 38% | 55.5% | 51.7% |
| Enrollment | 34 | top 95% | - | - |
Source: NCES Common Core of Data School-level CCD + state/national means from Public School Universe · 2024-25
17:1
Leaner classes than 30% of US schools, heavier class loads than most.
34
Bigger than 4% of US schools by enrollment, a small campus.
Equity indicators (what these measure)
Economic need
76.5%
free-lunch eligible
- 38% above the California average of 55.5%
Above the 40% Title I schoolwide threshold; federal funds support the whole school, not individual students.
Staffing depth
17:1
students per teacher
- 21% 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
35.3%
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
$10,212
per pupil, district-wide
- below California avg of $16,509
Well below the U.S. average per-pupil spend, a notably leaner funding position that may affect programs, facilities, and staffing.
Support staff
Counselors0.0 FTE
Student-support staffing from the Civil Rights Data Collection.
Discipline context
0
in-school suspensions + 1 out-of-school
Suspension rate: 0.0 per 100 students. Combined in-school and out-of-school rate: 2.9 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.
Programs
Funding & spending
District-wide per-pupil expenditure for Pacific Union Elementary, which includes Trillium Charter.
$10,212
Per student
-38%
vs California
Avg $16,509
-38%
vs U.S.
Avg $16,593
Revenue mix
Local 12.5%
State 69.8%
Federal 17.7%
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 Trillium Charter Compares to District-Mates
| School | Enrollment | Economic Profile | Student-Teacher Ratio |
|---|---|---|---|
| Pacific Union Elementary | Larger | Lower economic need | Higher S:T ratio |
Comparisons are relative to Trillium Charter's own figures; each column derives from NCES Common Core of Data.
Other Schools in This District
- Enrollment
- 534
- Students per teacher
- 19.1:1
- Resource Index
- 41/100
Similar elementary schools in Arcata
5 comparable elementary schools (grades K-5) serving the same city.
Pacific Union Elementary
Standard public school
534 students 19.1:1 students per teacher
Arcata Elementary
Standard public school
240 students 16:1 students per teacher
Coastal Grove Charter
Standard public school
235 students 16.8:1 students per teacher
Fuente Nueva Charter
Standard public school
150 students 25:1 students per teacher
Union Street Charter
Standard public school
99 students 19.8:1 students per teacher
Similar elementary 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 (~34 students)
Similar student-teacher ratio (~17:1)
Next steps
Verify locally before acting on Trillium Charter's federal record.
- Compare Trillium Charter against another school. Compare schools
- Pacific Union Elementary'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 Trillium Charter
How many students attend Trillium Charter?
Trillium Charter has 34 students enrolled. It is an elementary school in Arcata, CA.
What is the student-teacher ratio at Trillium Charter?
The student-teacher ratio at Trillium Charter is 17:1, which is 21% lower than the California average of 21.5:1 and 8% 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 Trillium Charter?
76.5% of students at Trillium Charter are eligible for free lunch, compared to the California average of 55.5%.
What is the Resource Investment Index for Trillium Charter?
Trillium Charter has a Resource Investment Index of 25/100 (lower reported resources relative to schools nationally) based on 3 factors: student-teacher ratio, attendance rates. Not a test-score or academic measure (national median ~41/100, see methodology).
How does Trillium Charter rank among elementary schools in Arcata?
By Resource Investment Index, Trillium Charter ranks #4 of 6 elementary schools in Arcata, CA. This compares federal resource and staffing data among local peers; it is not a test-score or academic ranking. See all elementary schools in Arcata on the city page.
Is Trillium Charter a good school?
Trillium Charter earns 25/100 on the Resource Investment Index, even as it posts class sizes smaller than 83% of California schools. It is also one of the smallest schools in California. 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 Pacific Union Elementary?
Besides Trillium Charter, Pacific Union Elementary also operates Pacific Union Elementary (534 students). See the Pacific Union Elementary 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.