The national Students’ Union has called demonstrations in more than 50 towns, its leader Tohil Delgado told predicting that thousands of students and teachers would join in despite looming exams.
“We have called this demonstration as an initial response to this attack on public education, which is without precedent in the past 35 years,” he said, citing reforms that protestors say are disrupting classes.
As Spain fights to stabilise its public finances, schools and universities have for months been complaining of shrinking budgets for research and extra work for teachers.
Since the last student marches on February 29, the government has announced a further three billion euros in cost-cutting reforms.
On April 20, the central government said it would let regional authorities expand class sizes by a fifth and raise university fees to an average 1,500 euros from 1,000 euros.
Protests in cities including Madrid and Barcelona are due to start at noon (1000 GMT) on Thursday, the union said.
Spain’s universities have been a traditional centre of protest since the time of General Francisco Franco’s 1939-1975 dictatorship.
The latest demonstrations are part of a wave of anger at the austerity measures launched since the conservative Popular Party of Prime Minister Mariano Rajoy took over the government in December.
In a broader protest, the movement known as the “indignant” on May 15 marks one year since it sprang up and occupied central Madrid for weeks with a tent city on the Puerta del Sol square.
The movement has promised four days of protests from May 12 to 15.
The “indignants” appear divided over their internal organization, however, as traditional labour unions take centre stage, mobilising huge protests.
Hundreds of thousands of people demonstrated during a general strike on March 29, and a strike across the whole education sector is planned for May 22. (AFP)