| Index | Decatur | Indiana | National |
| Average Test Scores | 40% | 46% | 48% |
| Student/Teacher ratio | 16:1 | 22:1 | 16:1 |
| Total public schools | 5 | 1,755 | 79,221 |
| Total private schools | 3 | 675 | 24,874 |
| Total post-secondary schools | n/a | 141 | 7,963 |

| Index | Decatur | Indiana | National |
| Completed 8th grade | 83.1% | 84.6% | 84.3% |
| Completed high school | 81.9% | 82.9% | 83.0% |
| Completed some college | 43.2% | 53.8% | 59.4% |
| Completed associate degree | 18.9% | 33.0% | 38.5% |
| Completed bachelors | 13.6% | 24.6% | 30.3% |
| Completed masters | 3.6% | 8.9% | 11.5% |
| Completed professional degree | 1.1% | 2.4% | 3.3% |
| Completed doctorate | 0.3% | 1.0% | 1.3% |
There are a total of 5 public schools, 3 private schools and n/a post-secondary schools in Decatur. Using the proficiency score averages, the average test scores for Decatur, IN schools is 40%. The average student to teacher ratio is 16:1. In Decatur, IN, an average of 83.1% of students have completed 8th grade and an average of 81.9% have completed high school.
| City | Population | Avg. Test Scores | National Avg. |
| Convoy, OH | 1,135 | 83% | 72.6% |
| Rockford, OH | 908 | 83% | 72.6% |
| Monroe, IN | 884 | 53% | 10.8% |
| Bluffton, IN | 10,527 | 53% | 10.4% |
| Berne, IN | 4,093 | 52% | 9.0% |
| Decatur, IN | 10,024 | 40% | 17.4% |
| City | Population | Avg. Test Scores | National Avg. |
| Hamburg, NY | 10,025 | 65% | 35.8% |
| Corte Madera, CA | 10,023 | 80% | 66.1% |
| Uniontown, PA | 10,028 | 46% | 5.2% |
| Winfield, IL | 10,018 | 54% | 12.0% |
| Cody, WY | 10,018 | 58% | 21.7% |
| Decatur, IN | 10,024 | 40% | 17.4% |