| School | Address | Town | County | |
|---|---|---|---|---|
| Ysgol Cei Newydd | Maes Yr Ysgol | Ceredigion | Select | |
| Ysgol Cenarth | Cenarth | Carmarthenshire | Select | |
| Ysgol Cerrigydrudion | Ffordd Yr Alwen | Corwen | Select | |
| Ysgol Clawdd Offa | By Plas Morfa Farm | Prestatyn | Denbighshire (Sir Ddinbych) | Select |
| Ysgol Clydau | Tregryn | Pembrokeshire | Select | |
| Ysgol Clywedog | Ruthin Road | Wrexham | Select | |
| Ysgol Comins Coch | Comins Coch | Ceredigion | Select | |
| Ysgol Corn Hir | Llangefni | Ynys Mon | Select | |
| Ysgol Craig y Deryn | Llanegryn | Llanegryn | Gwynedd | Select |
| Ysgol Craig Y Don | Clarence Drive | Conwy | Select |