| Index | Marissa | Illinois | National |
| Average Test Scores | 23% | 33% | 48% |
| Student/Teacher ratio | 22:1 | 18:1 | 16:1 |
| Total public schools | 2 | 3,938 | 79,221 |
| Total private schools | n/a | 1,438 | 24,874 |
| Total post-secondary schools | n/a | 306 | 7,963 |

| Index | Marissa | Illinois | National |
| Completed 8th grade | 78.5% | 86.2% | 84.3% |
| Completed high school | 78.3% | 84.7% | 83.0% |
| Completed some college | 50.2% | 61.8% | 59.4% |
| Completed associate degree | 22.1% | 40.7% | 38.5% |
| Completed bachelors | 11.6% | 32.9% | 30.3% |
| Completed masters | 3.2% | 12.7% | 11.5% |
| Completed professional degree | 1.1% | 3.4% | 3.3% |
| Completed doctorate | 0.0% | 1.2% | 1.3% |
There are a total of 2 public schools, n/a private schools and n/a post-secondary schools in Marissa. Using the proficiency score averages, the average test scores for Marissa, IL schools is 23%. The average student to teacher ratio is 22:1. In Marissa, IL, an average of 78.5% of students have completed 8th grade and an average of 78.3% have completed high school.
| City | Population | Avg. Test Scores | National Avg. |
| Smithton, IL | 4,157 | 61% | 27.1% |
| Freeburg, IL | 4,020 | 55% | 14.1% |
| St. Libory, IL | 607 | 50% | 4.2% |
| Oakdale, IL | 303 | 45% | 6.3% |
| Okawville, IL | 1,511 | 45% | 7.3% |
| Marissa, IL | 1,297 | 23% | 51.6% |
| City | Population | Avg. Test Scores | National Avg. |
| Renville, MN | 1,297 | 47% | 2.1% |
| Curtice, OH | 1,297 | 77% | 60.4% |
| Paducah, TX | 1,298 | 42% | 12.5% |
| Deville, LA | 1,298 | 76% | 58.3% |
| Big Rock, IL | 1,298 | 55% | 13.5% |
| Marissa, IL | 1,297 | 23% | 51.6% |