- Enrollment
- 75
- Students per teacher
- 8.3:1
- Resource Index
- 61/100
Elementary school (grades K-5) · Casa Grande, AZ
Mary C O'brien Elementary School
Federal NCES profile for Mary C O'brien Elementary School, including enrollment, faculty, free-lunch eligibility, demographics, and resource indicators - Resource Investment Index 42/100.
2024-25 NCES dataElementary school (grades K-5)NCES 040274000203
👥 S:T ratio 55
🌟 Gifted program 70
📋 Attendance 0
Scored 0–100 from federal NCES and CRDC indicators, resource allocation, not test scores. Full methodology →
The verdict
Mary C O'brien Elementary School earns 42/100 on the Resource Investment Index, with class sizes smaller than 88% of Arizona schools.
- #2 of 3
- elementary schools in Casa Grande · Resource Index
- 42
- Resource Index · Typical
- 11.2:1
- small classes for Arizona
- 51.7%
- free-lunch eligible
Mary C O'brien Elementary School has class sizes smaller than 88% of Arizona schools. Computed live against every Arizona school reporting to NCES.
By Resource Investment Index, Mary C O'brien Elementary School ranks #2 of 3 elementary schools in Casa Grande, AZ.
School address
District: Mary C O'brien Accommodation District (4435) · Arizona
NCES ID 040274000203 Verify on NCES CCD record →
CCD year-over-year · 2022-23 → 2023-24
+2 students YoY
Mary C O'brien Elementary School held near 122 students from 2022-23 to 2023-24 (+2 headcount).
Teacher FTE added 11.5 → 13.5 across the same CCD years.
Source: NCES Common Core of Data public-school universe (2022-23, 2023-24).
Steady CCD campus
+2 students YoY 040274000203 · Casa Grande, AZ Elementary · SMALL · TRAD
123 enr · 11.2:1 · 51.7% lunch · RII 42
Nearest enrollment peer: Villa Oasis Interscholastic Center for Education (Voice) (75 students)
Mary C O'brien Elementary School held near 122 students from 2022-23 to 2023-24 (+2 headcount). Teacher FTE added 11.5 → 13.5 across the same CCD years. Read with this school → · District book → · Arizona schools → · Find another →
How Mary C O'brien Elementary School compares
Mary C O'brien Elementary School held steady on CCD headcount: ratios and free-lunch share vs Arizona and U.S. means.
| Metric | This school | vs Arizona | Arizona avg | U.S. avg |
|---|---|---|---|---|
| Students per teacher | 11.2:1 | ▼ 34% | 17:1 | 15.7:1 |
| Free-lunch eligible | 51.7% | ▲ 7% | 48.3% | 51.7% |
| Enrollment | 123 | top 80% | - | - |
Source: NCES Common Core of Data School-level CCD + state/national means from Public School Universe · 2024-25
11.2:1
Leaner classes than 82% of US schools, among the more generously staffed nationally.
123
Bigger than 12% of US schools by enrollment, a small campus.
Equity indicators methodology
Economic need
51.7%
free-lunch eligible
- 7% above the Arizona average of 48.3%
Above the 40% Title I schoolwide threshold; federal funds support the whole school, not individual students.
Staffing depth
11.2:1
students per teacher
- 34% below state mean
Top 12% in Arizona - lower ratio than 88% of state schools
Well under the widely cited 15:1 individualized-attention benchmark, among the leaner class loads nationally.
Engagement
45.5%
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
$27,922
per pupil, district-wide
- above Arizona avg of $13,502
Well above the U.S. public-school average, reflecting substantially higher local or state investment per enrolled student.
Support staff
Counselors0.0 FTE
Student-support staffing from the Civil Rights Data Collection.
Discipline context
1
in-school suspensions + 1 out-of-school
Suspension rate: 0.8 per 100 students. Combined in-school and out-of-school rate: 1.6 per 100 students. Reported via the Civil Rights Data Collection.
Student demographics
Hispanic or Latino 52.8%
White 36.6%
Two or More 7.3%
American Indian / Alaska Native 2.4%
African American 0.8%
Largest group: Hispanic or Latino at 52.8% of enrollment.
Student-body diversity index 58.1/100
Simpson diversity index - at 58.1, Mary C O'brien Elementary School is more mixed than the Arizona school average of 47.2.
Programs
Gifted & talented Yes
District finance for Mary C O'brien Accommodation District (4435) reports $27,922 per pupil (NCES F-33) - open the district page for the full revenue mix.
How Mary C O'brien Elementary School Compares to District-Mates
| School | Enrollment | Economic Profile | Student-Teacher Ratio |
|---|---|---|---|
| Villa Oasis Interscholastic Center for Education (Voice) | Smaller | Similar economic need | Lower S:T ratio |
Comparisons are relative to Mary C O'brien Elementary School's own figures; each column derives from NCES Common Core of Data.
Other Schools in This District
Similar elementary schools in Casa Grande
1 comparable elementary schools (grades K-5) serving the same city.
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 (~123 students)
Frequently asked questions about Mary C O'brien Elementary School
How many students attend Mary C O'brien Elementary School?
Mary C O'brien Elementary School has 123 students enrolled. It is an elementary school in Casa Grande, AZ. CCD year-over-year: 120 (2022-23) → 122 (2023-24), nearly flat (+2).
What is the student-teacher ratio at Mary C O'brien Elementary School?
The student-teacher ratio at Mary C O'brien Elementary School is 11.2:1, which is 34% lower than the Arizona average of 17:1 and 29% 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 Mary C O'brien Elementary School?
51.7% of students at Mary C O'brien Elementary School are eligible for free lunch, compared to the Arizona average of 48.3%.
What is the racial and ethnic makeup of Mary C O'brien Elementary School?
The largest demographic group at Mary C O'brien Elementary School is Hispanic or Latino at 52.8% of enrollment, in Casa Grande, AZ. Its student body is more racially and ethnically mixed than most US schools, with a diversity index of 58.1/100.
What is the Resource Investment Index for Mary C O'brien Elementary School?
Mary C O'brien Elementary School has a Resource Investment Index of 42/100 (typical reported resources relative to schools nationally) based on 3 factors: student-teacher ratio, gifted-program reporting, chronic absenteeism. Not a test-score or academic measure (national median ~41/100, see methodology).
How does Mary C O'brien Elementary School rank among elementary schools in Casa Grande?
By Resource Investment Index, Mary C O'brien Elementary School ranks #2 of 3 elementary schools in Casa Grande, AZ. This compares federal resource and staffing data among local peers; it is not a test-score or academic ranking. See all elementary schools in Casa Grande on the city page.
What other schools are in Mary C O'brien Accommodation District (4435)?
Besides Mary C O'brien Elementary School, Mary C O'brien Accommodation District (4435) also operates Villa Oasis Interscholastic Center for Education (Voice) (75 students). See the Mary C O'brien Accommodation District (4435) district page for the complete list.