| Index | O'Fallon | Missouri | National |
| Average Test Scores | 61% | 44% | 48% |
| Student/Teacher ratio | 17:1 | 14:1 | 16:1 |
| Total public schools | 16 | 1,899 | 79,221 |
| Total private schools | 4 | 531 | 24,874 |
| Total post-secondary schools | 1 | 213 | 7,963 |
| Index | O'Fallon | Missouri | National |
| Completed 8th grade | 92.8% | 86.0% | 84.3% |
| Completed high school | 92.0% | 84.2% | 83.0% |
| Completed some college | 70.7% | 57.7% | 59.4% |
| Completed associate degree | 46.5% | 35.2% | 38.5% |
| Completed bachelors | 38.6% | 27.6% | 30.3% |
| Completed masters | 13.5% | 10.4% | 11.5% |
| Completed professional degree | 1.9% | 2.8% | 3.3% |
| Completed doctorate | 0.9% | 1.2% | 1.3% |
There are a total of 16 public schools, 4 private schools and 1 post-secondary schools in O'Fallon. Using the proficiency score averages, the average test scores for O'Fallon, MO schools is 61%. The average student to teacher ratio is 17:1. In O'Fallon, MO, an average of 92.8% of students have completed 8th grade and an average of 92.0% have completed high school.
| City | Population | Avg. Test Scores | National Avg. |
| Dardenne Prairie, MO | 13,385 | 73% | 51.0% |
| Lake St. Louis, MO | 16,357 | 71% | 48.4% |
| Weldon Spring, MO | 5,536 | 70% | 45.5% |
| Chesterfield, MO | 47,603 | 69% | 43.2% |
| Cottleville, MO | 5,439 | 69% | 43.1% |
| O'Fallon, MO | 88,132 | 61% | 27.1% |
| City | Population | Avg. Test Scores | National Avg. |
| Palm Coast, FL | 88,222 | 61% | 26.0% |
| Champaign, IL | 88,288 | 32% | 33.7% |
| Newton, MA | 88,322 | 73% | 52.5% |
| Reading, PA | 88,333 | 31% | 35.8% |
| Conroe, TX | 88,369 | 46% | 4.0% |
| O'Fallon, MO | 88,132 | 61% | 27.1% |
Here are the best places to live in Missouri
See the best places to live in O'Fallon
These are the largest cities in Missouri
Check out the 10 most dangerous cities in Missouri