High school · Philadelphia, PA
Building 21
- Grades
- 9–12
- Enrollment (2023-24)
- 382
- Regular attendance
- 60.3%
- District
- Philadelphia City
Regular attendance is the share of students present at least 90% of enrolled days (statewide average 79.6%). Source: Pennsylvania Future Ready PA Index, 2024-25; enrollment and grades from the U.S. Department of Education (NCES).
Academic proficiency
Share of students scoring proficient or advanced on Keystone exams (grade 11), Pennsylvania Future Ready PA Index, 2024-25. Black tick = state average.
More Philadelphia schools
Browse every School District of Philadelphia school, with the context a district-wide average hides, on the Philadelphia schools hub. See also Philadelphia property taxes and crime data.
Common questions
What grades does Building 21 serve?
Building 21 is a high school in the Philadelphia City School District, located in Philadelphia, PA, serving grades 9–12.
How many students attend Building 21?
About 382 students are enrolled at Building 21 (U.S. Department of Education NCES Common Core of Data, 2023-24 school year).
What is the attendance rate at Building 21?
60.3% of Building 21 students are regularly present, enrolled and attending at least 90% of school days, versus 79.6% statewide (Pennsylvania Future Ready PA Index, 2024-25).
How does Building 21 perform academically?
On Keystone exams (grade 11), 2.9% of Building 21 students scored proficient or advanced in math, and 24.2% in English/language arts (Pennsylvania Future Ready PA Index, 2024-25). District-wide results are on the Philadelphia City School District page.
Other Philadelphia schools
The School District of Philadelphia runs more than 200 schools. Browse them all, grouped by level, on the Philadelphia schools hub.
Free Newsletter
The NookLocal Digest
We work hard to only send quality information in our newsletter. Sign up!
Unsubscribe any time. See our Privacy Policy.
School identity, grades, and enrollment: U.S. Department of Education, NCES Common Core of Data. Regular attendance: Pennsylvania Future Ready PA Index (2024-25). Figures describe the school and may lag by a year or more: context for families, not a rating. Academic and safety detail is on the Philadelphia schools hub.