| Onalaska ISD, TX (District) |
| Onalaska School District, WA (District) |
| Onalaska School District, WI (District) |
| Onamia Public School District, MN (District) |
| Onaway Area Community School District, MI (District) |
| One City Preparatory Academy, WI (PSA) |
| One City Schools Inc, WI (PSA) |
| One City Senior Preschool, WI (PSA) |
| Oneida, TN (District) |
| Oneida, WI (ISD) |
| Oneida City School District, NY (District) |
| Oneida County, ID (ISD) |
| Oneida County, NY (ISD) |
| Oneida County District, ID (District) |
| Oneida Township S/D #3, MI (District) |
