Students in Chile resumed their campaign for free education with marches in major cities on Wednesday.
Police estimated the number of protesters in Santiago at more than 37,000 but organisers say 80,000 people took to the streets.
There also were protests in other cities, including Valparaiso, Concepcion, Temuco and Valdivia.
The BBC reports students have been staging protests for free, high-quality education since 2011. Wednesday's marches were the second nationwide protest this year.
Although Chile's education system is regarded by many as one of the best in Latin America, students argue it is deeply unfair.
Middle-class students have access to some of the best schooling in the region, while the poor have to be content with under-funded state schools. There are no free universities.
The BBC reports the campaign started with a wave of mass demonstrations in 2011, which carried on throughout 2012.