The research strategy consisted of three components. First, an experimental designed evaluation to estimate the causal impact of the new pedagogical approach on scholastic achievement of the students. Second, surveys of principals, teachers, parents and students were carried out to obtain the socio-demographic information of the schools and the students’ families. Third, a qualitative evaluation was carried out to further understand the context of the treatment and the evaluation. The experimental design covered 106 schools in the Department of Lima where the random assignment of the treatment was at the school level, that is, 53 treated and 53 non-treated schools, with a total of 2,771 third grade students in the 106 schools. The sample was stratified according to school location (urban, metropolitan, and rural). For
budgetary reasons only two classrooms per school were included. In the schools where there were more than two classes, the two classes included in the evaluation were chosen randomly in the presence of the principal.