| Index | Defiance | Iowa | National |
| Average Test Scores | n/a | 69% | 48% |
| Student/Teacher ratio | n/a | 13:1 | 16:1 |
| Total public schools | n/a | 1,101 | 79,221 |
| Total private schools | n/a | 208 | 24,874 |
| Total post-secondary schools | n/a | 96 | 7,963 |

| Index | Defiance | Iowa | National |
| Completed 8th grade | 85.1% | 89.2% | 84.3% |
| Completed high school | 82.9% | 87.7% | 83.0% |
| Completed some college | 27.6% | 59.8% | 59.4% |
| Completed associate degree | 17.1% | 38.4% | 38.5% |
| Completed bachelors | 8.3% | 27.2% | 30.3% |
| Completed masters | 2.2% | 8.7% | 11.5% |
| Completed professional degree | 0.0% | 2.7% | 3.3% |
| Completed doctorate | 0.0% | 1.1% | 1.3% |
There are a total of n/a public schools, n/a private schools and n/a post-secondary schools in Defiance. Using the proficiency score averages, the average test scores for Defiance, IA schools is n/a. The average student to teacher ratio is n/a. In Defiance, IA, an average of 85.1% of students have completed 8th grade and an average of 82.9% have completed high school.
| City | Population | Avg. Test Scores | National Avg. |
| Harlan, IA | 4,917 | 81% | 68.1% |
| Irwin, IA | 336 | 80% | 66.7% |
| Manning, IA | 1,603 | 76% | 57.8% |
| Dow City, IA | 449 | 75% | 55.2% |
| Dunlap, IA | 1,246 | 70% | 44.8% |
| Defiance, IA | 224 | n/a |
| City | Population | Avg. Test Scores | National Avg. |
| Climax, MN | 224 | 40% | 17.2% |
| Coffman Cove, AK | 224 | 50% | 4.2% |
| Old Harbor, AK | 223 | 50% | 4.2% |
| Climax Springs, MO | 223 | 33% | 32.3% |
| Glenford, OH | 225 | 82% | 70.8% |
| Defiance, IA | 224 | n/a |