| Index | Greencastle | Missouri | National |
| Average Test Scores | n/a | 44% | 48% |
| Student/Teacher ratio | n/a | 14:1 | 16:1 |
| Total public schools | n/a | 1,899 | 79,221 |
| Total private schools | n/a | 531 | 24,874 |
| Total post-secondary schools | n/a | 213 | 7,963 |
| Index | Greencastle | Missouri | National |
| Completed 8th grade | 76.2% | 86.0% | 84.3% |
| Completed high school | 72.0% | 84.2% | 83.0% |
| Completed some college | 29.4% | 57.7% | 59.4% |
| Completed associate degree | 13.1% | 35.2% | 38.5% |
| Completed bachelors | 7.0% | 27.6% | 30.3% |
| Completed masters | 2.8% | 10.4% | 11.5% |
| Completed professional degree | 0.9% | 2.8% | 3.3% |
| Completed doctorate | 0.0% | 1.2% | 1.3% |
There are a total of n/a public schools, n/a private schools and n/a post-secondary schools in Greencastle. Using the proficiency score averages, the average test scores for Greencastle, MO schools is n/a. The average student to teacher ratio is n/a. In Greencastle, MO, an average of 76.2% of students have completed 8th grade and an average of 72.0% have completed high school.
| City | Population | Avg. Test Scores | National Avg. |
| Green City, MO | 538 | 51% | 5.7% |
| Unionville, MO | 1,888 | 50% | 3.5% |
| Novinger, MO | 347 | 40% | 17.2% |
| Milan, MO | 2,513 | 31% | 35.9% |
| Greencastle, MO | 181 | n/a |
| City | Population | Avg. Test Scores | National Avg. |
| Glacier View, AK | 181 | 50% | 4.2% |
| San Geronimo, CA | 181 | 51% | 6.3% |
| Geraldine, MT | 180 | 50% | 4.2% |
| Galt, MO | 180 | 43% | 11.5% |
| Malta Bend, MO | 182 | 35% | 27.1% |
| Greencastle, MO | 181 | n/a |
Here are the best places to live in Missouri
These are the 10 cheapest cities in Missouri
Check out the 10 safest cities in Missouri
Most Dangerous Cities In The US