Tens of thousands of striking school teachers converged on the capital to press demands for higher wages. The 40,000 teachers marched on the capital Monday, five days after beginning a nationwide walkout to demand a minimum wage of 640 australs ($90) a month for the country's 500,000 primary and secondary school teachers. An earlier strike that began March 14 at the opening of the Argentine public school year lasted six weeks until the government ordered teachers to begin work while negotiations continued. Negotiations later broke off. Union leader Marcos Garcetti and Labor Minister Ideler Tonelli negotiated for an hour on Monday without reaching an agreement, union sources said. About 7.2 million schoolchildren aged three to 18 have been affected by the walkout, which has generally not affected private schools.