| School | Address | Town | County | |
|---|---|---|---|---|
| Ysgol Craig Yr Wylfa | Francis Road | Ceredigion | Select | |
| Ysgol Crud Y Werin | Aberdaron | Gwynedd | Select | |
| Ysgol Crug Glas | Croft Street | Swansea | Select | |
| Ysgol Cwm Banwy Church in Wales Voluntary Aided School | Llangadfan | Welshpool | Powys | Select |
| Ysgol Cwm Brombil | Bertha Road | Port Talbot | Select | |
| Ysgol Cybi | Garreglwyd Road | Caergybi | Isle of Anglesey (Ynys Mon) | Select |
| Ysgol Cymerau | Ffordd Mela | Gwynedd | Select | |
| Ysgol Cynddelw | New Road | Llangollen | Select | |
| Ysgol Cystennin | The Old Highway | Conwy | Select | |
| Ysgol Dafydd Llwyd | Plantation Lane | Powys | Select |