| Index | Diagonal | Iowa | National |
| Average Test Scores | 78% | 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 | Diagonal | Iowa | National |
| Completed 8th grade | 85.4% | 89.2% | 84.3% |
| Completed high school | 81.7% | 87.7% | 83.0% |
| Completed some college | 46.3% | 59.8% | 59.4% |
| Completed associate degree | 28.8% | 38.4% | 38.5% |
| Completed bachelors | 12.5% | 27.2% | 30.3% |
| Completed masters | 2.9% | 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 Diagonal. Using the proficiency score averages, the average test scores for Diagonal, IA schools is 78%. The average student to teacher ratio is n/a. In Diagonal, IA, an average of 85.4% of students have completed 8th grade and an average of 81.7% have completed high school.
| City | Population | Avg. Test Scores | National Avg. |
| Mount Ayr, IA | 1,988 | 83% | 73.4% |
| Lenox, IA | 1,446 | 73% | 52.6% |
| Afton, IA | 901 | 71% | 47.4% |
| Diagonal, IA | 475 | 78% | 61.5% |
| City | Population | Avg. Test Scores | National Avg. |
| Garden Valley, ID | 475 | 60% | 24.0% |
| Kinde, MI | 475 | 35% | 28.1% |
| Bonanza, OR | 475 | 41% | 15.1% |
| Glasco, KS | 474 | 38% | 21.9% |
| Bancroft, NE | 474 | 47% | 2.1% |
| Diagonal, IA | 475 | 78% | 61.5% |
Here are the best places to live in Iowa
These are the 10 cheapest cities in Iowa
Check out the 10 safest cities in Iowa
These are the largest cities in Iowa