- Enrollment
- 3,074
- Students per teacher
- 21.8:1
- Resource Index
- 38/100
High school (grades 9-12) · Allentown, PA
Building 21 Allentown
Federal NCES profile for Building 21 Allentown, including enrollment, faculty, free-lunch eligibility, demographics, and resource indicators - Resource Investment Index 42/100.
2024-25 NCES dataHigh school (grades 9-12)NCES 420228007623
👥 S:T ratio 41
🌟 Gifted program 70
🎓 Counselors 59
📋 Attendance 0
Scored 0–100 from federal NCES and CRDC indicators, resource allocation, not test scores. Full methodology →
The verdict
Building 21 Allentown earns 42/100 on the Resource Investment Index, with class sizes larger than 73% of Pennsylvania schools.
- #4 of 5
- high schools in Allentown · Resource Index
- 42
- Resource Index · Typical
- 14.8:1
- large classes for Pennsylvania
- 97.3%
- free-lunch eligible
Building 21 Allentown has class sizes larger than 73% of Pennsylvania schools. Computed live against every Pennsylvania school reporting to NCES.
By Resource Investment Index, Building 21 Allentown ranks #4 of 5 high schools in Allentown, PA.
School address
District: Allentown City Sd · Pennsylvania
NCES ID 420228007623 Verify on NCES CCD record →
CCD year-over-year · 2022-23 → 2023-24
-28 students YoY
Building 21 Allentown shrank from 439 students in 2022-23 to 411 in 2023-24 (-6.4%).
Teacher FTE lost 28.0 → 26.0 across the same CCD years.
Source: NCES Common Core of Data public-school universe (2022-23, 2023-24).
Shrinking CCD campus
-28 students YoY 420228007623 · Allentown, PA High · SMALL · TRAD
415 enr · 14.8:1 · 97.3% lunch · RII 42
Nearest enrollment peer: William Allen Hs (3,074 students)
Building 21 Allentown shrank from 439 students in 2022-23 to 411 in 2023-24 (-6.4%). Teacher FTE lost 28.0 → 26.0 across the same CCD years. Read with this school → · District book → · Pennsylvania schools → · Find another →
Building 21 Allentown in the enrollment neighbourhood
Fall enrollment among this campus and nearest district peers
- William Allen
William Allen Hs
3,074 students
- Louis E Dieruf
Louis E Dieruff Hs
1,914 students
- South Mountain 972
South Mountain Ms
972 students
- Francis D Raub 876
Francis D Raub Ms
876 students
- Brigadier Gene 807
Brigadier General Anna Mae Hays El Sch
807 students
- This school 415
Building 21 Allentown
415 students
What this shows Building 21 Allentown reports 415 students on the CCD universe file.
How Building 21 Allentown compares
Building 21 Allentown is a shrinking campus on CCD: ratios and free-lunch share vs Pennsylvania and U.S. means.
| Metric | This school | vs Pennsylvania | Pennsylvania avg | U.S. avg |
|---|---|---|---|---|
| Students per teacher | 14.8:1 | ▲ 9% | 13.6:1 | 15.7:1 |
| Free-lunch eligible | 97.3% | ▲ 67% | 58.1% | 51.7% |
| Enrollment | 415 | top 58% | - | - |
Source: NCES Common Core of Data School-level CCD + state/national means from Public School Universe · 2024-25
14.8:1
Leaner classes than 49% of US schools, a middle-of-the-pack class size.
415
Bigger than 50% of US schools by enrollment, mid-sized for the country.
Equity indicators methodology
Economic need
97.3%
free-lunch eligible
- 67% above the Pennsylvania average of 58.1%
Above the 40% Title I schoolwide threshold; federal funds support the whole school, not individual students.
Staffing depth
14.8:1
students per teacher
- 9% above state mean
Top 73% in Pennsylvania - lower ratio than 27% of state schools
Close to the 15:1 benchmark most often cited for individualized attention.
Engagement
65.1%
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
$17,939
per pupil, district-wide
- below Pennsylvania avg of $18,725
Close to the U.S. public-school average per-pupil spend.
Support staff
Counselors2.0 FTE
Per 208 students, the combined health-and-guidance staffing load for this school.
Discipline context
1
in-school suspensions + 14 out-of-school
Suspension rate: 0.2 per 100 students. Combined in-school and out-of-school rate: 3.6 per 100 students. Reported via the Civil Rights Data Collection.
Student demographics
Hispanic or Latino 81.2%
African American 9.4%
Two or More 5.1%
White 3.1%
Asian 1.0%
Native Hawaiian / Pacific Islander 0.2%
Largest group: Hispanic or Latino at 81.2% of enrollment.
Student-body diversity index 32.8/100
Simpson diversity index - at 32.8, Building 21 Allentown is less mixed than the Pennsylvania school average of 37.3.
Programs
AP program Not offered
Gifted & talented Yes
District finance for Allentown City Sd reports $17,939 per pupil (NCES F-33) - open the district page for the full revenue mix.
How Building 21 Allentown Compares to District-Mates
| School | Enrollment | Economic Profile | Student-Teacher Ratio |
|---|---|---|---|
| William Allen Hs | Larger | Lower economic need | Higher S:T ratio |
| Louis E Dieruff Hs | Larger | Similar economic need | Higher S:T ratio |
| South Mountain Ms | Larger | Similar economic need | Similar S:T ratio |
| Francis D Raub Ms | Larger | Similar economic need | Higher S:T ratio |
| Brigadier General Anna Mae Hays El Sch | Larger | Similar economic need | Similar S:T ratio |
Comparisons are relative to Building 21 Allentown's own figures; each column derives from NCES Common Core of Data.
Other Schools in This District
- Enrollment
- 1,914
- Students per teacher
- 18.1:1
- Resource Index
- 48/100
- Enrollment
- 972
- Students per teacher
- 13.7:1
- Resource Index
- 38/100
- Enrollment
- 876
- Students per teacher
- 16.5:1
- Resource Index
- 36/100
- Enrollment
- 807
- Students per teacher
- 15.8:1
- Resource Index
- 17/100
Similar high schools in Allentown
4 comparable high schools (grades 9-12) serving the same city.
Parkland Hs
Standard public school
3,279 students 15.2:1 students per teacher
William Allen Hs
Standard public school
3,074 students 21.8:1 students per teacher
Louis E Dieruff Hs
Standard public school
1,914 students 18.1:1 students per teacher
Salisbury Shs
Standard public school
546 students 15.6:1 students per teacher
Nationwide high 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 (~415 students)
Frequently asked questions about Building 21 Allentown
How many students attend Building 21 Allentown?
Building 21 Allentown has 415 students enrolled. It is a high school in Allentown, PA. CCD year-over-year: 439 (2022-23) → 411 (2023-24), down 28.
What is the student-teacher ratio at Building 21 Allentown?
The student-teacher ratio at Building 21 Allentown is 14.8:1, which is 9% higher than the Pennsylvania average of 13.6:1 and 6% lower than the national average of 15.7:1.
What percentage of students receive free lunch at Building 21 Allentown?
97.3% of students at Building 21 Allentown are eligible for free lunch, compared to the Pennsylvania average of 58.1%.
What is the racial and ethnic makeup of Building 21 Allentown?
The largest demographic group at Building 21 Allentown is Hispanic or Latino at 81.2% of enrollment, in Allentown, PA.
What is the Resource Investment Index for Building 21 Allentown?
Building 21 Allentown has a Resource Investment Index of 42/100 (typical 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 Building 21 Allentown rank among high schools in Allentown?
By Resource Investment Index, Building 21 Allentown ranks #4 of 5 high schools in Allentown, PA. This compares federal resource and staffing data among local peers; it is not a test-score or academic ranking. See all high schools in Allentown on the city page.
What other schools are in Allentown City Sd?
Besides Building 21 Allentown, Allentown City Sd also operates William Allen Hs (3,074 students), Louis E Dieruff Hs (1,914 students), and South Mountain Ms (972 students). See the Allentown City Sd district page for the complete list.