More than 50,000 Chilean youths marched through central Santiago yesterday to demand free, good-quality public education in a drawn-out dispute with the government of President Sebastian Pinera.“The time has come to fight, not to negotiate,” some students said in their banners.Demonstrators walked past the Dario Salas School, where three minors have been on hunger strike for 21 days to support student demands.Chilean student protests started three months ago and have already led to a change of minister.In Chile, most school education and the whole of the university system requires the payment of monthly fees.Last week, close to 900 people were arrested and 90 police officers were injured in student protests.