Supply teachers' training worry - NUT
Classroom standards could be hit because supply teachers are not given enough opportunity for professional development, a union has warned.
Nearly 10% of school lessons are taught by supply teachers, according to education watchdog Estyn.
Owen Hathway from NUT Cymru said there were concerns supply teachers are not being given the training they need.
The Welsh government said it was developing ways for all teachers to "develop their own practice".
Mr Hathway said supply teachers were concerned about training opportunities.
"We have to ensure that, at every lesson, those who are leading the classes are able to deliver it with the sort of standard quality that we'd expect," he said.
"And if we have a certain percentage of lessons taught by supply teachers who are not able to access the same level of professional development, then obviously consistency amongst that teaching standard is going to waver."
The Welsh assembly's education committee is looking at supply teaching.
Its survey of more than 900 pupils found nearly a quarter were taught by a supply teacher every week and 80% said they learned less with a supply teacher than with their usual teacher.
Meilyr Rowlands, who becomes Wales' new chief inspector of schools next month, said it was unacceptable supply teachers were not given the support they need.
"The expectations on education and on teachers now are so high that we just can't afford to not give regular training for supply teachers, so something has to be done," he told AMs.
One problem is that schools, supply teacher agencies and councils refuse to take responsibility for training, and supply teachers also miss out on important feedback from their work, he said.
'Time and effort'
Cardiff supply teacher Mike Hyde said teachers could not afford to attend all the training days offered to them or they did not have the time.
"You're trying to pick up bits of the training that you need via other teaching staff that have undertaken the training. And, obviously then, it's quite often a watered down version and you end up with more questions you want to ask," he said.
Teaching agency, E-Qual, set up by former supply teacher Carolyn Rahman, offers free training days for supply teachers to keep them up-to-date with developments and maintain standards.
But Ms Rahman said many other agencies did not provide this.
"I'd imagine it's cost, money, maybe time and effort," she said.
"We know our teachers and schools very well and we're a team that likes to share good practice. We like to know our teachers are comfortable and happy in their work."
MY LIFE AS A SUPPLY TEACHER
Supply teachers Catherine Davies and Yasmin Jones said they were sometimes not told until the last minute they were needed, with little time to prepare.
"If things are put in place for supply teachers, things can run a lot smoother," said Ms Davies.
Ms Jones added: "The job is a lot harder than people initially think."
Mr Hathway said supply teachers themselves see a real deficiency and it can hit morale.
"Despite being excellent teachers in their own right, the longer they spend in supply, the lack of time they have for professional development is a real concern for them," he said.
The Welsh government said head teachers needed to ensure supply teachers were properly qualified and registered.
"As we roll out the New Deal for the education workforce we will be developing ways for all teachers, including supply teachers, to reflect upon and develop their own practice," said a spokesman.