The Auditor General for Wales, Huw Vaughan Thomas, says there is an 'increasing reliance' on supply teachers in our schools.
Figures show one in 10 Welsh schoolchildren are taught by supply staff, as a report out today says children's progress is being hampered by teacher absence.
To use supply cover efficiently and effectively schools need to better understand the causes of teacher absence and to develop more effective cover arrangements.
These actions will not only save schools money but also have a positive impact on pupil attainment.
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Wintry showers to continue through the weekend and warnings of gales
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Cold, breezy and generally cloudy at first with further wintry outbreaks on the hills