| School | Address | Town | County | |
|---|---|---|---|---|
| Ysgol Dyffryn Aeron | Felinfach | Lampeter | Select | |
| Ysgol Dyffryn Aman | Margaret Street | Carmarthenshire | Select | |
| Ysgol Dyffryn Cledlyn VC CiW | Drefach | Llanybydder | Select | |
| Ysgol Dyffryn Conwy | Nebo Road | Llanrwst | Conwy | Select |
| Ysgol Dyffryn Ial | Allt Yr Efail | Sir Ddinbych | Select | |
| Ysgol Dyffryn Nantlle | Ffordd Y Brenin | Gwynedd | Select | |
| Ysgol Dyffryn Ogwen Bethesda | Ffordd Coetmor | Gwynedd | Select | |
| Ysgol Dyffryn Trannon | Trefeglwys | Powys | Select | |
| Ysgol Dyffryn yr Enfys | Ffordd Llanrwst | Dolgarrog | Select | |
| Ysgol Edmwnd Prys | Gellilydan | Gwynedd | Select |