Protests here Thursday by striking high school students unhappy with Chile's underfunded public education system ended in confrontations with riot police.

Departing from their usual practice of mounting a single march, the students organized more than a dozen separate processions to various municipal government buildings in greater Santiago.

The national student strike followed three weeks of protests that included school occupations punctuated by police operations to evict the occupiers.

Thursday's disturbances were localized in downtown Santiago and near the town hall in the capital municipality of Providencia.

Around 3,000 students were gathered in front of the Santiago mayor's office when some of them tried to start marching down the city's main thoroughfare, the Alameda.

Police resorted to tear gas and water cannon when the students ignored several warnings to disperse.

The protesters responded by pelting the cops with rocks and other projectiles.

The crowd outside the Providence town hall was estimated at around 5,000.

Students also organized significant protests in other Chilean cities, including Valparaiso and Valdivia.

President Sebastian Piñera sought to downplay Thursday's protests, while emphasizing his administration's commitment to education.

"It's small groups," government spokesman Andres Chadwick said, adding that the "country is very tired" of the student demonstrations.

Chilean students took to the streets in large numbers more than 40 times in 2011 to denounce a highly stratified education system that funnels state subsidies to private institutions even as public schools in poor areas struggle.

The protests have continued this year and another nationwide mobilization is planned for next Tuesday.

Chile's public schools and universities were neglected by the 1973-1990 dictatorship of the late Gen. Augusto Pinochet, who embraced doctrinaire free market policies.

Private schools mushroomed under the military regime and the trend continued after democracy was restored, even during the 1990-2010 tenure of the center-left Concertacion coalition.

The students want public primary and secondary schools to be administered centrally, not at the level of individual municipalities, as is currently the case, as well as the elimination of school fees.

The movement also demands an end to for-profit universities and a reduction in the high cost of college, which forces many students to take on large debt.

Piñera, a right-wing billionaire, has taken some steps to make college more affordable for low-income students and is now asking Congress to pass a tax reform bill that would generate as much as $1 billion in additional education funding.

Critics dismiss that figure as woefully inadequate. EFE