Nod y system gategoreiddio yw pennu’r cymorth sydd ei angen ar ein hysgolion er mwyn iddynt wella. Mae'n cynnig dull cyfannol o wella ysgolion, sy’n galluogi i gyd-destun yr ysgol ac ystod eang o wybodaeth gael eu hystyried wrth bennu dyfarniad ynghylch hunanwerthusiad yr ysgol a'i chapasiti i wella.
The purpose of the categorisation system is to identify the level of support our schools need to improve.It offers a holistic approach to school improvement, which allows the context of the school and a broad range of information to be taken into account when determining a judgement on the school`s self-evaluation and capacity to improve.