There are claims our children's education is being put at risk by an increase in teacher absence.
Reports published by the Wales Audit Office and education inspectorate Estyn found that nearly one in 10 lessons are being covered by staff who are not the usual class teacher.
From 2011 - 2012, £54 million was spent on providing supply to fill in for teachers who were off ill, out training or even attending meetings.
But organisations providing cover staff say supply teachers play an important role; while the National Union of Teachers says there are 'a variety of issues' affecting classroom teaching and teacher absence is not solely to blame.
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