- Enrollment
- 2,563
- Students per teacher
- 26.7:1
- Resource Index
- 48/100
Elementary school (grades K-5) · Diamond Bar, CA
Castle Rock Elementary
Federal NCES profile for Castle Rock Elementary, including enrollment, faculty, free-lunch eligibility, demographics, and resource indicators - Resource Investment Index 26/100.
2024-25 NCES dataElementary school (grades K-5)NCES 064128006833
👥 S:T ratio 0
🌟 Gifted program 30
🎓 Counselors 0
📋 Attendance 72
Scored 0–100 from federal NCES and CRDC indicators, resource allocation, not test scores. Full methodology →
The verdict
Castle Rock Elementary earns 26/100 on the Resource Investment Index, with class sizes larger than 86% of California schools.
- #6 of 7
- elementary schools in Diamond Bar · Resource Index
- 26
- Resource Index · Lower
- 26.3:1
- large classes for California
- 24.9%
- free-lunch eligible
Castle Rock Elementary has class sizes larger than 86% of California schools. Computed live against every California school reporting to NCES.
By Resource Investment Index, Castle Rock Elementary ranks #6 of 7 elementary schools in Diamond Bar, CA.
School address
District: Walnut Valley Unified · California
NCES ID 064128006833 Verify on NCES CCD record →
CCD year-over-year · 2022-23 → 2023-24
+45 students YoY
Castle Rock Elementary grew from 646 students in 2022-23 to 691 in 2023-24 (+7.0%).
Teacher FTE held 26.2 → 26.4 across the same CCD years.
Source: NCES Common Core of Data public-school universe (2022-23, 2023-24).
Growing CCD campus
+45 students YoY 064128006833 · Diamond Bar, CA Elementary · MID · TRAD
684 enr · 26.3:1 · 24.9% lunch · RII 26
Nearest enrollment peer: Diamond Bar High (2,563 students)
Castle Rock Elementary grew from 646 students in 2022-23 to 691 in 2023-24 (+7.0%). Teacher FTE held 26.2 → 26.4 across the same CCD years. Read with this school → · District book → · California schools → · Find another →
Castle Rock Elementary in the enrollment neighbourhood
Fall enrollment among this campus and nearest district peers
- Diamond Bar Hi
Diamond Bar High
2,563 students
- Walnut High
Walnut High
2,148 students
- Chaparral Midd
Chaparral Middle
1,349 students
- Suzanne Middle
Suzanne Middle
1,190 students
- South Pointe M 979
South Pointe Middle
979 students
- This school 684
Castle Rock Elementary
684 students
What this shows Castle Rock Elementary reports 684 students on the CCD universe file.
How Castle Rock Elementary compares
Castle Rock Elementary is a growing campus on CCD: ratios and free-lunch share vs California and U.S. means.
| Metric | This school | vs California | California avg | U.S. avg |
|---|---|---|---|---|
| Students per teacher | 26.3:1 | ▲ 22% | 21.5:1 | 15.7:1 |
| Free-lunch eligible | 24.9% | ▼ 55% | 55.5% | 51.7% |
| Enrollment | 684 | top 25% | - | - |
Source: NCES Common Core of Data School-level CCD + state/national means from Public School Universe · 2024-25
26.3:1
Leaner classes than 4% of US schools, heavier class loads than most.
684
Bigger than 79% of US schools by enrollment, mid-sized for the country.
Equity indicators methodology
Economic need
24.9%
free-lunch eligible
- 55% 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
26.3:1
students per teacher
- 22% above state mean
Top 86% in California - lower ratio than 14% of state schools
Well above 20:1, one of the more stretched staffing loads nationally relative to enrollment.
Engagement
11.1%
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
$13,963
per pupil, district-wide
- below California avg of $18,665
Well below the U.S. average per-pupil spend, a notably leaner funding position that may affect programs, facilities, and staffing.
Support staff
Counselors1.0 FTE
Per 684 students, the combined health-and-guidance staffing load for this school.
Discipline context
0
in-school suspensions + 0 out-of-school
Suspension rate: 0.0 per 100 students. Combined in-school and out-of-school rate: 0.0 per 100 students. Reported via the Civil Rights Data Collection.
Student demographics
Asian 70.2%
Hispanic or Latino 19.3%
Two or More 5.4%
White 2.9%
African American 1.5%
Native Hawaiian / Pacific Islander 0.6%
American Indian / Alaska Native 0.1%
Largest group: Asian at 70.2% of enrollment.
Student-body diversity index 46.6/100
Simpson diversity index - at 46.6, Castle Rock Elementary is about as mixed as the California school average of 46.0.
Programs
District finance for Walnut Valley Unified reports $13,963 per pupil (NCES F-33) - open the district page for the full revenue mix.
How Castle Rock Elementary Compares to District-Mates
| School | Enrollment | Economic Profile | Student-Teacher Ratio |
|---|---|---|---|
| Diamond Bar High | Larger | Similar economic need | Similar S:T ratio |
| Walnut High | Larger | Similar economic need | Lower S:T ratio |
| Chaparral Middle | Larger | Similar economic need | Higher S:T ratio |
| Suzanne Middle | Larger | Similar economic need | Similar S:T ratio |
| South Pointe Middle | Larger | Similar economic need | Similar S:T ratio |
Comparisons are relative to Castle Rock Elementary's own figures; each column derives from NCES Common Core of Data.
Other Schools in This District
- Enrollment
- 2,148
- Students per teacher
- 23.1:1
- Resource Index
- 52/100
- Enrollment
- 1,349
- Students per teacher
- 30.7:1
- Resource Index
- 41/100
- Enrollment
- 1,190
- Students per teacher
- 27:1
- Resource Index
- 43/100
- Enrollment
- 979
- Students per teacher
- 27.2:1
- Resource Index
- 47/100
Similar elementary schools in Diamond Bar
6 comparable elementary schools (grades K-5) serving the same city.
Evergreen Elementary
Standard public school
709 students 25.3:1 students per teacher
Quail Summit Elementary
Standard public school
696 students 27.8:1 students per teacher
Maple Hill Elementary
Standard public school
556 students 27.8:1 students per teacher
Pantera Elementary
Standard public school
512 students 24.4:1 students per teacher
Golden Springs Elementary
Standard public school
388 students 24.3:1 students per teacher
Armstrong Elementary
Standard public school
251 students 17.9:1 students per teacher
Nationwide elementary schools with similar size or staffing
Out-of-state peers matched by enrollment and by student-teacher ratio, not the same-city or same-district lists above.
Similar enrollment (~684 students)
Frequently asked questions about Castle Rock Elementary
How many students attend Castle Rock Elementary?
Castle Rock Elementary has 684 students enrolled. It is an elementary school in Diamond Bar, CA. CCD year-over-year: 646 (2022-23) → 691 (2023-24), up 45.
What is the student-teacher ratio at Castle Rock Elementary?
The student-teacher ratio at Castle Rock Elementary is 26.3:1, which is 22% higher than the California average of 21.5:1 and 68% higher than the national average of 15.7:1.
What percentage of students receive free lunch at Castle Rock Elementary?
24.9% of students at Castle Rock Elementary are eligible for free lunch, compared to the California average of 55.5%.
What is the racial and ethnic makeup of Castle Rock Elementary?
The largest demographic group at Castle Rock Elementary is Asian at 70.2% of enrollment, in Diamond Bar, CA.
What is the Resource Investment Index for Castle Rock Elementary?
Castle Rock Elementary has a Resource Investment Index of 26/100 (lower reported resources relative to schools nationally) based on 4 factors: student-teacher ratio, gifted-program reporting, counselor availability, chronic absenteeism. Not a test-score or academic measure (national median ~41/100, see methodology).
How does Castle Rock Elementary rank among elementary schools in Diamond Bar?
By Resource Investment Index, Castle Rock Elementary ranks #6 of 7 elementary schools in Diamond Bar, 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 Diamond Bar on the city page.
What other schools are in Walnut Valley Unified?
Besides Castle Rock Elementary, Walnut Valley Unified also operates Diamond Bar High (2,563 students), Walnut High (2,148 students), and Chaparral Middle (1,349 students). See the Walnut Valley Unified district page for the complete list.