A breakdown of exclusion figures shows there were 699 exclusions for violent assaults on teachers in 2003-4 - up 185 on the previous year. But unions say teachers feel powerless to fend off their attackers and the punishments - usually a suspension of five days or fewer - are not tough enough.
There were 49 permanent exclusions, 48 for six days or more, and most - 502 in total - were barred from school for five days or fewer in 2003. Cardiff, the biggest LEA, recorded the highest number of attacks (153), followed by Newport, Caerphilly, Rhondda Cynon Taf and Swansea. Six-school Blaenau Gwent, an area of high deprivation, had one of the lowest totals with fewer than five exclusions. Gwynedd had none.
Janet Ryder, shadow education minister for Plaid Cymru, which asked for the figures, said they were alarming. She called on education and lifelong learning minister Jane Davidson to set up a working group to examine the problem of pupil violence.
Ms Ryder said: "Surveys show classroom behaviour is the number one concern of teaching staff. There has been work on education attainment but not enough on making our classrooms safe."
Brian Rowlands, Welsh secretary of the Association of School and College Leaders Cymru, said: "Schools are a microcosm of society and, sadly, reflect the resort to violence as a solution to problems.
"Parents share a huge responsibility, but some are only too willing to criticise and verbally attack the profession."
Geraint Davies, secretary of teaching union the NASUWT Cymru, has previously advised teachers to call police every time a pupil is violent towards them.
An Assembly government spokesperson said it was reviewing guidance on how teachers should intervene physically in violent incidents involving pupils.
She added: "Violence against teachers is one symptom of the need to address behaviour in schools. We have various plans to tackle this problem - for example, through our inclusion and pupil support guidance, implementation of parenting orders and parenting contracts, and new measures proposed in the forthcoming Education Bill on reaffirming the right of school staff to discipline."