| Sierra Sands Unified, CA (District) |
| Sierra Unified, CA (District) |
| Sierra Vista Charter School Inc., AZ (PSA) |
| Sierra Vista Unified District, AZ (District) |
| Sierra-Plumas Joint Unified, CA (District) |
| Sigel Township S/D #3F, MI (District) |
| Sigel Township S/D #4F, MI (District) |
| Sigel Township S/D #6, MI (District) |
| Sigma Academy for Leadership and Early Middle College, MI (PSA) |
| Signal Hill SD 181, IL (District) |
| Signature School Inc, IN (District) |
| Sigourney Comm School District, IA (District) |
| Sikeston R-6, MO (District) |
| Silex R-I, MO (District) |
| Silo, OK (District) |
