The police used tear gas to disperse students and teachers protesting the changes the government wants to make to recruit teachers in public schools.
The clashes broke out when hundreds of protesters attempted to cross the ranks of riot police deployed near Parliament, beating police buses lined up in the blockade.
"I'm a full-time teacher, but we're by their side," Venetia Reppa told reporters on the back, with a stun gun shot by police officers behind her, talking about her part-time colleagues. Because, he added, the proposed reform "affects" everyone.
The Ministry of Education is preparing to present to Parliament a draft law on recruitment in public education, which deplores the teachers' unions, does not take sufficient account of the past experience of new recruits.
Public institutions in this sector have been severely affected by cuts in public spending for Greece in exchange for international assistance to cope with the debt crisis.