While going to public school is free, there are other fees that must be paid throughout the school year (user fees levied by teachers in order for the students to participate in class activities and projects). The cumulative effect of these fees makes it cost-prohibitive for poor families to attend these overcrowded classrooms, so many drop out mid school year or don't even bother going at all.
The school the EAC children attend has a rule that user fees are not to be charged by the teachers. So once tuition is paid, the students can participate in all school and extra-curricular activities. When occasional extra fees are neccessary (for instance purchase of special equipment, though this is rare), the school offers as much assistance as possible to financially-challenged students.
The curriculum for a private and public school is the same, following the guidelines put in place by the Department of Education in the Philippines.