Serving 382 students in grades 9-12, Building 21 ranks in the bottom 50% of all schools in Pennsylvania for overall test scores (math proficiency is bottom 50%, and reading proficiency is bottom 50%).
The percentage of students achieving proficiency in math is 6-9% (which is lower than the Pennsylvania state average of 38%). The percentage of students achieving proficiency in reading/language arts is 20-24% (which is lower than the Pennsylvania state average of 55%).
The student:teacher ratio of 15:1 is higher than the Pennsylvania state level of 13:1.
Quick Stats (2025)
- Grades: 9-12
- Enrollment: 382 students
- Student:Teacher Ratio: 15:1
- Graduation Rate: 90-94% (Top 50% in PA)
- Math Proficiency: 6-9% (Top 1%)
- Reading Proficiency: 20-24% (Btm 50%)
- Science Proficiency: ≤5% (Btm 50%)
- Source: National Center for Education Statistics (NCES), PA Dept. of Education
Top Rankings
Building 21 ranks among the top 20% of public schools in Pennsylvania for:
Category
Attribute
Percent Eligible For Free Lunch
School Overview
Building 21's student population of 382 students has grown by 14% over five school years.
The teacher population of 25 teachers has grown by 31% over five school years.
Grades Offered
Grades 9-12
(No virtual instruction)
(No virtual instruction)
Total Students
382 students
Gender %
Total Classroom Teachers
25 teachers
School Rankings
The diversity score of Building 21 is 0.19, which is less than the diversity score at state average of 0.59. The school's diversity has stayed relatively flat over five school years.
Math Test Scores (% Proficient)
(20-21)6-9%
38%
Reading/Language Arts Test Scores (% Proficient)
20-24%
55%
Science Test Scores (% Proficient)
≤5%
57%
Student : Teacher Ratio
15:1
13:1
American Indian
n/a
n/a
Asian
1%
5%
Hispanic
8%
15%
Black
90%
14%
White
n/a
61%
Hawaiian
n/a
n/a
Two or more races
1%
5%
All Ethnic Groups
Graduation Rate
90-94%
87%
Eligible for Free Lunch
100%
60%
School Statewide Testing
School District Name
Source: National Center for Education Statistics (NCES), PA Dept. of Education
Profile last updated: 02/09/2025
Frequently Asked Questions
What schools are Building 21 often compared to?
Building 21is often viewed alongside schools like Lankenau High School by visitors of our site.
What percent of students have achieved state testing proficiency in math and reading?
6-9% of students have achieved math proficiency (compared to the 38% PA state average), while 20-24% of students have achieved reading proficiency (compared to the 55% PA state average).
What is the graduation rate of Building 21?
The graduation rate of Building 21 is 90-94%, which is higher than the Pennsylvania state average of 87%.
How many students attend Building 21?
382 students attend Building 21.
What is the racial composition of the student body?
90% of Building 21 students are Black, 8% of students are Hispanic, 1% of students are Asian, and 1% of students are Two or more races.
What is the student:teacher ratio of Building 21?
Building 21 has a student ration of 15:1, which is higher than the Pennsylvania state average of 13:1.
What grades does Building 21 offer ?
Building 21 offers enrollment in grades 9-12 (No virtual instruction).
What school district is Building 21 part of?
Building 21 is part of Philadelphia City School District.
In what neighborhood is Building 21 located?
Building 21 is located in the North Philadelphia neighborhood of Philadelphia, PA. There are 106 other public schools located in North Philadelphia.
School Reviews
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