National city placement
One campus shapes the city average
According to NCES CCD 2024-25, O Fallon has more public-school enrollment than 69% of the 4,487 US cities in this directory. O Fallon High School enrolls 36.1% of O Fallon's public-school students. That is enough concentration for one institution to pull the citywide enrollment, staffing, and Resource Index averages toward its own profile. The smaller campuses below should therefore be compared directly rather than inferred from the headline mean; their grade configurations and program footprints can be materially different even inside the same district.
Combined-grade campuses shape the local portfolio
5 of O Fallon's 10 listed schools use NCES's combined or “other” grade-level classification. Citywide averages therefore blend campuses serving unusually broad or nonstandard grade spans with conventional elementary, middle, and high schools. Grade configuration is a first-order comparison here, not a minor label.
Campus spread matters more than the city mean
The 20-point gap between J Emmett Hinchcliffe Sr Elem Sch and Joseph Arthur Middle School shows the range hidden by O Fallon's average Resource Investment Index. The city figure is useful for national placement, but families ultimately choose among campuses with different grade spans, enrollment, district affiliations, and reported support fields. Start with schools serving the relevant grade level, then compare the index components rather than assuming the city average describes any one classroom.