That represents a steep rise on the 4,600 instances recorded the year before, which was itself a big jump from the 2,800 in 2010.
"These incidents are apparently just the tip of the iceberg, as reporting procedures vary," warned OAJ chair Olli Luukkainen.
The union leader is concerned that teachers’ right to work free of threats and insults is being compromised. Unrest in the classroom can also, according to the union, adversely affect the majority of students who would like to learn in peace.
The union would like Parliament to strengthen teachers’ powers, pupils’ responsibilities and co-operation between schools and parents. OAJ also says that savings drives in local authorities could compromise the quality of education on offer.
Some 100 head shop stewards answered the OAJ survey.