Building 21 vs Mastery CS-Francis D. Pastorius Elementary
A head-to-head comparison of two schools in Pennsylvania, United States, 986 m apart, using official American 2025 data. The better value in each row is highlighted.
Building 21
Philadelphia · Public high · Grades 9–12
371 students
Mastery CS-Francis D. Pastorius Elementary
Philadelphia · Charter elementary · Grades K–8
647 students
| Measure | Building 21 Philadelphia, Pennsylvania | Mastery CS-Francis D. Pastorius Elementary Philadelphia, Pennsylvania |
|---|---|---|
| Success Index (US) | 9 Lower 50% | 15 Lower 50% |
| State rank | #611 of 618 | #1544 of 1,627 |
| National rank | #16656 of 16,910 | #47444 of 50,301 |
| Sector | Public | Charter |
| Type | High | Elementary |
| Year range | Grades 9–12 | Grades K–8 |
| Students | 371 | 647 |
| Enrollment | 371 | 647 |
| Free/reduced-price lunch | 103% | 99.5% |
| Students per teacher | 20.6 | 15.0 |
| Reading proficiency | 32% | 31% |
| Math proficiency | 7.5% | 15% |
| city | Philadelphia | Philadelphia |
| state | Pennsylvania | Pennsylvania |
| Website | – | – |
The verdict
- •Mastery CS-Francis D. Pastorius Elementary scores higher on the Success Index (US) (15.4 vs 9.2).
- •Mastery CS-Francis D. Pastorius Elementary does better on math proficiency (15% vs 7.5%).
- •Building 21 does better on reading proficiency (32% vs 31%).
- •Mastery CS-Francis D. Pastorius Elementary does better on community advantage (fewer free/reduced-price lunch) (99.5% vs 103%).
- •Mastery CS-Francis D. Pastorius Elementary does better on students per teacher (15.0 vs 20.6).
- •Mastery CS-Francis D. Pastorius Elementary is the larger school with 647 students compared with 371.
- •Building 21 is a public school while Mastery CS-Francis D. Pastorius Elementary is a charter school, so fees and admission rules differ.
The Success Index (US) summarises published results and context from official data. It does not measure teaching quality or fit. Methodology.
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Frequently asked questions
Is Building 21 better than Mastery CS-Francis D. Pastorius Elementary?
On the Success Index (US), Mastery CS-Francis D. Pastorius Elementary ranks higher (15.4 vs 9.2 out of 100). The index is built from published results and context data, not from teaching quality or fit, so visit both schools before deciding.
How far apart are Building 21 and Mastery CS-Francis D. Pastorius Elementary?
About 986 m in a straight line, between Philadelphia and Philadelphia in Pennsylvania.
Which has the better Enrollment?
Building 21: 371. Mastery CS-Francis D. Pastorius Elementary: 647. Students enrolled in the latest NCES directory year.
How do Building 21 and Mastery CS-Francis D. Pastorius Elementary rank in Pennsylvania?
Building 21 is 611th of 618 and Mastery CS-Francis D. Pastorius Elementary is 1544th of 1,627 among high schools in Pennsylvania on the 2025 Success Index (US).