| Index | Hartly | Delaware | National |
| Average Test Scores | 62% | 44% | 48% |
| Student/Teacher ratio | n/a | 16:1 | 16:1 |
| Total public schools | n/a | 191 | 79,221 |
| Total private schools | n/a | 129 | 24,874 |
| Total post-secondary schools | n/a | 20 | 7,963 |

| Index | Hartly | Delaware | National |
| Completed 8th grade | 77.4% | 86.3% | 84.3% |
| Completed high school | 77.4% | 85.3% | 83.0% |
| Completed some college | 61.3% | 57.7% | 59.4% |
| Completed associate degree | 48.4% | 38.2% | 38.5% |
| Completed bachelors | 38.7% | 30.5% | 30.3% |
| Completed masters | 12.9% | 12.4% | 11.5% |
| Completed professional degree | 3.2% | 3.5% | 3.3% |
| Completed doctorate | 0.0% | 1.7% | 1.3% |
There are a total of n/a public schools, n/a private schools and n/a post-secondary schools in Hartly. Using the proficiency score averages, the average test scores for Hartly, DE schools is 62%. The average student to teacher ratio is n/a. In Hartly, DE, an average of 77.4% of students have completed 8th grade and an average of 77.4% have completed high school.
| City | Population | Avg. Test Scores | National Avg. |
| Frederica, DE | 980 | 77% | 60.4% |
| Church Hill, MD | 891 | 57% | 18.8% |
| Felton, DE | 1,237 | 56% | 17.0% |
| Clayton, DE | 3,485 | 51% | 7.0% |
| Smyrna, DE | 12,109 | 50% | 4.3% |
| Hartly, DE | 170 | 62% | 29.2% |
| City | Population | Avg. Test Scores | National Avg. |
| Richey, MT | 170 | 50% | 4.2% |
| Iola, TX | 170 | 57% | 18.8% |
| Orchard, TX | 170 | 37% | 22.9% |
| Deer Creek, OK | 170 | 47% | 2.1% |
| Akhiok, AK | 170 | 50% | 4.2% |
| Hartly, DE | 170 | 62% | 29.2% |