| Index | Cotter | 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 | Cotter | Iowa | National |
| Completed 8th grade | 89.7% | 89.2% | 84.3% |
| Completed high school | 89.7% | 87.7% | 83.0% |
| Completed some college | 27.6% | 59.8% | 59.4% |
| Completed associate degree | 6.9% | 38.4% | 38.5% |
| Completed bachelors | 0.0% | 27.2% | 30.3% |
| Completed masters | 0.0% | 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 Cotter. Using the proficiency score averages, the average test scores for Cotter, IA schools is n/a. The average student to teacher ratio is n/a. In Cotter, IA, an average of 89.7% of students have completed 8th grade and an average of 89.7% have completed high school.
| City | Population | Avg. Test Scores | National Avg. |
| Morning Sun, IA | 742 | 75% | 56.3% |
| Letts, IA | 347 | 72% | 50.7% |
| Kalona, IA | 2,588 | 69% | 43.8% |
| Wayland, IA | 1,188 | 67% | 39.6% |
| Winfield, IA | 1,070 | 66% | 37.0% |
| Cotter, IA | 21 | n/a |
| City | Population | Avg. Test Scores | National Avg. |
| Wolford, ND | 22 | 60% | 25.0% |
| Shoshone, CA | 19 | 50% | 4.2% |
| Coulterville, CA | 24 | 30% | 37.5% |
| Inkster, ND | 24 | 51% | 6.3% |
| Weston, CO | 16 | 45% | 6.3% |
| Cotter, IA | 21 | n/a |