Bydd diwrnod HMS ychwanegol yn digwydd bob tymor yr haf ar gyfer y tair blynedd nesaf, yn benodol i roi mwy o amser i athrawon ar gyfer eu dysgu proffesiynol. Mae hynny'n rhan o becyn cymorth i helpu ysgolion i baratoi ar gyfer y Cwricwlwm newydd i Gymru, a fydd yn cael ei roi ar waith o 2022 ymlaen.
An extra INSET day will take place each summer term for the next three years specifically to give teachers more time for their professional learning. This is part of a package of support to help schools prepare for the new Curriculum for Wales, which will be rolled out from 2022.