| Index | Greencastle | Pennsylvania | National |
| Average Test Scores | 69% | 55% | 48% |
| Student/Teacher ratio | 19:1 | 16:1 | 16:1 |
| Total public schools | 4 | 2,563 | 79,221 |
| Total private schools | 2 | 1,626 | 24,874 |
| Total post-secondary schools | n/a | 406 | 7,963 |
| Index | Greencastle | Pennsylvania | National |
| Completed 8th grade | 88.2% | 86.9% | 84.3% |
| Completed high school | 85.4% | 85.6% | 83.0% |
| Completed some college | 49.7% | 53.6% | 59.4% |
| Completed associate degree | 31.5% | 37.4% | 38.5% |
| Completed bachelors | 25.7% | 29.3% | 30.3% |
| Completed masters | 11.4% | 11.5% | 11.5% |
| Completed professional degree | 3.9% | 3.3% | 3.3% |
| Completed doctorate | 0.6% | 1.4% | 1.3% |
There are a total of 4 public schools, 2 private schools and n/a post-secondary schools in Greencastle. Using the proficiency score averages, the average test scores for Greencastle, PA schools is 69%. The average student to teacher ratio is 19:1. In Greencastle, PA, an average of 88.2% of students have completed 8th grade and an average of 85.4% have completed high school.
| City | Population | Avg. Test Scores | National Avg. |
| Sabillasville, MD | 390 | 65% | 35.4% |
| Fayetteville, PA | 2,855 | 64% | 32.3% |
| McConnellsburg, PA | 1,030 | 63% | 31.6% |
| Mercersburg, PA | 1,673 | 62% | 29.0% |
| Waynesboro, PA | 10,898 | 61% | 27.8% |
| Greencastle, PA | 4,008 | 69% | 44.4% |
| City | Population | Avg. Test Scores | National Avg. |
| Esparto, CA | 4,009 | 27% | 44.1% |
| Clay Center, KS | 4,007 | 44% | 8.6% |
| Fredericktown, MO | 4,006 | 42% | 12.5% |
| Akron, PA | 4,006 | 65% | 34.4% |
| Ovilla, TX | 4,010 | 64% | 32.3% |
| Greencastle, PA | 4,008 | 69% | 44.4% |
Here are the best places to live in Pennsylvania
See the best places to live in Greencastle
Check out the 10 safest cities in Pennsylvania
Most Dangerous Cities In The US