Enrollment
251
Elementary
DISTRICT 456 · STATE 465
SCHOOL COMMUNITY·POMONA UNIFIED·NCES 063132004836
Armstrong Elementary
22750 Beaverhead Dr., Diamond Bar, CA 91765 · (909) 397-4563 · Los Angeles County
GRADES KG–06ELEMENTARY21-SUBURBTITLE IREGULAR SCHOOL251 STUDENTS
Student : Teacher
18.6:1
14 FTE teachers
DISTRICT 21.2:1 · STATE 22.3:1
Free / Reduced Lunch
67%
168 students
DISTRICT 87% · STATE 65%
Community
0
0 members
Enrollment and student:teacher ratio compared against other elementary schools. Free/Reduced Lunch and demographics compared against all schools.
Enrollment by grade, 2024-25
| Grade | Students | Share |
|---|---|---|
| Kindergarten | 67 | 27% |
| Grade 1 | 31 | 12% |
| Grade 2 | 35 | 14% |
| Grade 3 | 31 | 12% |
| Grade 4 | 37 | 15% |
| Grade 5 | 26 | 10% |
| Grade 6 | 24 | 10% |
This year's kindergarten class (67) is 179% larger than its 6th grade class (24).
Student demographics
60%Diversity index
The chance that two students picked at random belong to different racial or ethnic groups.
DISTRICT 28% · STATE 62% · US 70%
Student head counts by race/ethnicity from federal NCES enrollment data. District, state, and US figures are each group's share of all public school students in that area (US excludes territories). Very small groups may be suppressed in the source, so categories do not always sum exactly to total enrollment.
Gender split
Test scores
CAASPP 2024-25 . % met or exceeded standardEnglish Language Arts
47.4%
CA avg 49.1% . -2.6pp since 2014
Math
29.3%
CA avg 37.7% . -8.7pp since 2014
What this means: On the CAASPP, California's statewide test, about 47 of every 100 students at this school read and write at grade level and about 29 of 100 do math at grade level. Across all California schools, those numbers are about 49 and 38. Reading and writing scores are down about 3 points since 2014, while math scores are down about 9 points.
Performance levels, 2024-25
| Subject | Standard Exceeded | Standard Met | Standard Nearly Met | Standard Not Met |
|---|---|---|---|---|
| English Language Arts | 25.0% | 22.4% | 23.3% | 29.3% |
| Math | 11.2% | 18.1% | 31.9% | 38.8% |
Share of tested students at each CAASPP level. Each student counts in one level, so a row adds to about 100%.
CAASPP results by year
| School year | English Language Arts | Math |
|---|---|---|
| 2024-25 | 47.4% | 29.3% |
| 2023-24 | 50.4% | 40.9% |
| 2022-23 | 54.3% | 39.8% |
| 2021-22 | 50.3% | 34.5% |
| 2018-19 | 67.1% | 43.3% |
| 2017-18 | 52.0% | 45.1% |
| 2016-17 | 47.4% | 34.3% |
| 2015-16 | 48.0% | 35.0% |
| 2014-15 | 50.0% | 38.0% |
% met or exceeded standard, all students and all tested grades.
Source: CAASPP. All students, all grades. See all years and grades →
BeatsExpectations
Demographically-adjusted score · methodologyTier
AS EXPECTED
Performing as predicted given the school's student profile
Actual proficiency
42.5%
composite math + reading, all grades
Predicted
40.3%
based on CA schools with similar FRL share
Beats by
+2.2pp
above demographic expectation
What this means: About 42% of students here test proficient in math and reading, compared with the roughly 40% typical for California schools with a similar share of low-income students. BeatsExpectations measures results against demographically similar schools rather than by raw scores, and this school falls within the typical range, neither among California's top nor bottom 10%.
BeatsExpectations runs a per-state regression of proficiency on free/reduced-lunch share, then scores each school by residual. How this is calculated →
Schools most like Armstrong Elementary
Armstrong Elementary's state test result (42.5% proficient) is higher than 4 of the 5 schools below with a result.
| School | Students | Low-income | Proficient |
|---|---|---|---|
| Armstrong Elementary this school | 251 | 66.9% | 42.5% |
| Hollywood Park Elementary Sacramento | 268 | 70.9% | 24.9% |
| Spring Valley Elementary San Francisco | 234 | 68.4% | 31.9% |
| Juarez (Benito) Elementary Cerritos | 295 | 72.5% | 35.9% |
| Valley View Acad of Tech and Creative Lrng (TK-6) Duarte | 317 | 61.2% | 55.4% |
| Canoas Elementary San Jose | 282 | 71.6% | 32.9% |
Matched among California elementary schools on enrollment, the share of students from low-income families (eligible for free or reduced-price lunch), and racial and ethnic makeup. Proficient is the average share of students meeting the state standard across all of the school's state tests in 2023-24 and 2024-25, the same combined score our test-score rankings use. Online schools and schools serving specialized populations are not matched.
Where Armstrong Elementary ranks
Among elementary schools| Measure | This school | In California | In Los Angeles County |
|---|---|---|---|
| State test proficiency ranked highest first | 42.5% | #2,271 of 5,151 | #541 of 1,126 |
| Math proficiency ranked highest first | 29.3% | #3,297 of 5,172 ▼ 1,185 | #859 of 1,129 ▼ 362 |
| Reading proficiency ranked highest first | 47.4% | #2,241 of 5,172 ▼ 370 | #527 of 1,129 ▼ 113 |
| 3-year test score change ranked biggest drop first | -4.1pp | #718 of 5,116 | #109 of 1,116 |
| Enrollment ranked largest first | 251 | #5,112 of 5,915 | #1,151 of 1,300 |
| Students per teacher ranked fewest first | 18.6:1 | #404 of 5,352 | #117 of 1,213 |
| Diversity index ranked most diverse first | 59.9% | #1,843 of 5,354 | #279 of 1,214 |
| Free and reduced lunch ranked highest share first | 66.9% | #3,124 of 5,625 | #877 of 1,276 |
| Enrollment change since 2017-18 ranked steepest decline first | -20.3% | #1,398 of 3,837 | #489 of 947 |
Ranked against other public elementary schools. Online schools are left out of every list, and test-score lists leave out schools that serve specialized populations. Each rank links to the full list. Arrows under a test-score rank show places moved since the prior test year, among schools tested both years.
4-year change
SY 2020-21 vs SY 2024-25Enrollment
251
-40 (-14%) vs 2020
-42% since 1990-91, when it was 434
Student : Teacher
18.6:1
was 22.4:1
Source: NCES Common Core of Data
Enrollment and staffing by year
| School year | Students | Teachers (FTE) | Students per teacher | Free and reduced lunch |
|---|---|---|---|---|
| 2024-25 | 251 | 13.5 | 18.6:1 | 67% (168) |
| 2023-24 | 249 | 12 | 20.8:1 | 69% (172) |
| 2022-23 | 257 | 14 | 18.4:1 | 67% (173) |
| 2020-21 | 291 | 13 | 22.4:1 | 75% (217) |
| 2017-18 | 315 | 14 | 22.5:1 | 63% (198) |
| 2015-16 | 406 | 14 | 29.0:1 | 54% (220) |
| 2010-11 | 292 | N/A | N/A | 34% (98) |
| 2000-01 | 509 | 25 | 20.4:1 | 22% (111) |
| 1990-91 | 434 | 18 | 24.1:1 | N/A |
Source: NCES Common Core of Data. Rows are the federal collections on file for Armstrong Elementary.
Since 2017-18: students down 20% (315 to 251); teachers down 4% (14 to 13.5).
About Armstrong Elementary
Armstrong Elementary is a low-enrollment elementary school with its address in Diamond Bar, California. The school enrolls 251 students, from kindergarten through 6. An average school in this group (elementary schools in California) has about 465 students.
Pomona Unified has 20,422 students in 37 schools, and Armstrong Elementary is one of those schools.
Armstrong Elementary is 60% Hispanic by enrollment. Smaller groups are 15% Asian, 10% White, 9% multiracial, and 6% Black. County-wide, 48% of Los Angeles County residents are Hispanic. The school's diversity index is 60%, meaning two students picked at random have a 60% chance of belonging to different racial or ethnic groups.
At Armstrong Elementary, 13.5 full-time-equivalent teachers work with students, a ratio of about 18.6:1. That is lower than the 22.3:1 average for elementary schools in California. Roughly 67% of the student body qualifies for free or reduced-price lunch. That tracks the 70% average for public schools in Los Angeles County.
Given its share of students eligible for free or reduced-price lunch, Armstrong Elementary would be expected to post about 40.3%. Its actual average proficiency rate on state tests is 42.5%.
Los Angeles County has these Census figures: the median household income is $90,112, about 36% of adults have at least a bachelor's degree, and roughly 10% of residents are in poverty. In all, Los Angeles County has 2,244 public schools and roughly 1,265,907 students.
Of nearby public schools, Lorbeer Middle is the closest, at about 0.6 miles. Armstrong Elementary has at least 8 other public schools within five miles. Among 9 nearby schools that report test results, Armstrong Elementary ranks 8th on proficiency.
NCES lists the school's locale as Suburb: Large. That means it sits in a suburban area outside a principal city, within an urbanized area with a population of 250,000 or more.
Federal data show a 14% enrollment decrease, from 291 in 2020-21 to 251 in 2024-25. Students per teacher fell from 22.4 in 2020-21 to 18.6 in 2024-25.
Conversations here can range across enrollment questions, class placement, and PTA news. Reviews and ratings from people who know the school are welcome.
Los Angeles County at a glance
View full county profilePopulation
9,808,667
Census ACS
Median income
$90,112
Household, ACS
Bachelor's+
36%
Adults 25+
Poverty rate
10%
Below federal line
Schools in county
2,244
1,265,907 students
Quick facts
Related schools
Other schools in Pomona Unified
- Garey HighHigh · 1,567 students
- Diamond Ranch HighHigh · 1,542 students
- School of Extended Educational OptionsCombined · 1,204 students
- Pomona HighHigh · 993 students
- Ganesha HighHigh · 895 students
- Vejar ElementaryElementary · 741 students
Other schools in Diamond Bar
- Diamond Bar HighHigh · 2,563 students
- Chaparral MiddleMiddle · 1,349 students
- Evergreen ElementaryElementary · 709 students
- Quail Summit ElementaryElementary · 696 students
- Lorbeer MiddleMiddle · 688 students
- Castle Rock ElementaryElementary · 684 students
Other Armstrong Elementary schools
9 other US public schools in 8 states are named Armstrong Elementary. Armstrong Elementary is the 9th largest of the 10.
- Armstrong Elementary SchoolCONROE, TX · 616 students
- Armstrong ElementaryEastover, NC · 456 students
- Armstrong ElementaryGreenville, SC · 435 students
- Armstrong Elementary SchoolDALLAS, TX · 431 students
- ARMSTRONG ELEM.HAZELWOOD, MO · 361 students
Nearby schools
- Lorbeer Middle0.6 mi · 688
- Golden Springs Elementary1.0 mi · 388
- Pantera Elementary1.7 mi · 512
- Maple Hill Elementary1.7 mi · 556
- Chaparral Middle1.8 mi · 1,349
- Quail Summit Elementary1.8 mi · 696
Frequently asked questions
About Armstrong ElementaryWhat is the total enrollment at Armstrong Elementary?
Armstrong Elementary enrolls approximately 251 students in grades KG-06.
What age range does Armstrong Elementary serve?
Armstrong Elementary serves students from grade KG through grade 06.
What is the student-teacher ratio at Armstrong Elementary?
The student-to-teacher ratio at Armstrong Elementary is approximately 18.6:1 (14 FTE teachers).
What is the student diversity at Armstrong Elementary?
Student demographics at Armstrong Elementary are roughly 10% White, 60% Hispanic, 6% Black, 15% Asian, 9% Two or more.
Who oversees Armstrong Elementary?
Armstrong Elementary is overseen by Pomona Unified in Los Angeles County.
Data sourceSchool profile facts are sourced from the NCES. Community content is posted by allk12 members.