President Juan Manuel Santos already has offered to cancel the plan, but nevertheless, about a half-million students from Colombia's 32 public universities have been on strike for the past month protesting the measure. The plan was presented with no student input to Congress where Santos has a broad majority. In Bogota, students on Thursday gathered in the downtown Plaza Bolivar, singing, chanting and waving signs with slogans like "We do not educate human capital, we educate human beings." Police reinforced security in the capital. Female students in the march responded by handing out flowers to the police. Similar protests were held in other cities, including the northwestern city of Medellin and the southwestern city of Cali. Santos said he would withdraw the proposal if the students ended their demonstrations. "You called for this strike to withdraw the reform and we have responded positively," he said. "We will withdraw the reform if you end the strike and return to classes." Santos invited protesters and other groups to sit down "and talk about what is needed in our higher education system, point by point." The students said they would hold a national assembly on Saturday to decide if the boycott should be ended. Withdrawing the proposal from Congress "is a demagogic move by the president ... so they can carry out a new reform and ignore us," 24 year-old college student Leonardo Gonzalez told AFP. "Education is not a service, it's a right," said another student, 16 year-old Mercedes Ruiz. Protests in Chile over past six months demanding more government support for education have rocked the administration of conservative President Sebastian Pinera.