| San Luis Obispo ESA, CA (ISD) |
| San Luis Valley Boces, CO (District) |
| San Luis Valley Boces, CO (District) |
| San Marcos Cisd, TX (District) |
| San Marcos Unified, CA (District) |
| San Marino Unified, CA (District) |
| San Mateo County Office of Education, CA (District) |
| San Mateo ESA, CA (ISD) |
| San Mateo Union High, CA (District) |
| San Mateo-Foster City, CA (District) |
| San Miguel County, CO (ISD) |
| San Miguel County, NM (ISD) |
| San Miguel Joint Union, CA (District) |
| San Pasqual Union Elementary, CA (District) |
| San Pasqual Valley Unified, CA (District) |
