The objective of this paper is to analyze the differences in efficiency and its explanatory factors of students according to their membership in public and private schools using PISA 2012 data for Colombia. The methodology used has been, non-parametric order-m and the meta-frontier approach. A second stage analysis was also used to determine the explanatory factors of efficiency. The main results obtained were as follows: i) the existence of efficiency differences between public and private schools; ii) the influence of the student and school effects as components of inefficiency; iii) the identification of positive influence on the efficiency of students' participation in single-parent or nuclear families in relation to another kind of guardianship, the influence of parent training, the student's belonging to the degree he studies, the best climate in the classroom and the location of the school in the case of public ownership. The size of the school has not been significant.