Building 21
Score 2.6/100: better than 2% of Pennsylvania high schools on 2024-25 state tests. Schools are only compared with others of the same type in the same state. How we score schools
Performance (state tests, 2024-25)
% proficient or advanced on state tests in Pennsylvania, all students. Colored bars are green when the school is at or above the average for similar Pennsylvania schools.
Results over time
How this school's published results have moved year by year.
All 3 published results by grade and test
As published by Pennsylvania Department of Education. "Hidden" means the state didn't publish the result to protect student privacy.
| Subject | Grade | Test | Result | Students tested |
|---|---|---|---|---|
| English language arts | High school | Keystone | 24.2 | 66 |
| Math | High school | Keystone | 2.9 | 68 |
| Science | High school | Keystone | 3.1 | 65 |
School profile
- Grades
- 9-12
- Students
- 382
- Type
- High school
- Charter school
- No
- Program
- Regular
Students
District and location
Contact
Philadelphia, PA 19138
"Typical" is the middle (median) high school in Pennsylvania. Higher or lower is not in itself better or worse. Address, phone and website are as the state reported them to the U.S. Department of Education for 2024-25, so check with the school before visiting. School details: U.S. Department of Education, Common Core of Data (enrollment 2023-24).
Nearby high schools
Straight-line distance. Check the district's attendance zones: living close to a school doesn't guarantee a place.
Explore schools around Philadelphia
Location
Official sources
Every figure on this page comes from published government data. Check the originals here; we refresh when states release new results.
U.S. Department of Education, National Center for Education Statistics, Common Core of Data (CCD): school directory, grades served, enrollment and free/reduced-price lunch, 2023-24 and 2024-25. Spotted a mistake? Tell us.
Building 21 at a glance
Building 21 is a public high school in Philadelphia, Pennsylvania, serving grades 9-12. It is part of the Philadelphia City SD school district. It has about 382 students (a typical Pennsylvania high school has 577).
In 2024-25 state tests, 24% in English language arts (similar schools: 62%) and 3% in math (similar schools: 44%) reached the state standard (% proficient or advanced). On our score, which compares it only with other Pennsylvania high schools, it scores 2.6 out of 100: better than 2% of them, ranking #578 of 593. Its English language arts result was broadly unchanged from the year before. This overview is generated automatically from published state and federal data; figures are rounded, and you can check the originals via the official sources above.
Page updated 2026-10-12.