The double-shift schooling system has been widely used to expand student enrollments and
thereby to achieve the objective of 00Education for All.00 Despite the advantages of the double-shift
schooling system, there may be negative externalities in academic achievement between the students
from different schooling sessions. For instance, teacher effectiveness may decrease in the afternoon
shift; which may lead to a reduction in the quality of teaching. In addition, students0
concentration
may be lower in the afternoon, which in turn may affect the ability to learn new material and, thus,
result in lower academic performance by students in the afternoon shift.
This paper examines the double-shift schooling system in Mexico, where the school administration
assigns children to the different schooling sessions. The non-random assignment of children to
different schooling shifts results in differences in the performance score gap between students in the
morning and in the afternoon shifts. As a result, high ability students are granted admission into
the morning shift, while low ability students are assigned to the afternoon session. As a result, these
factors could result in an unequal distribution of educational opportunities across different groups
of students.
This study analyzes academic performance of students from different schooling shifts using the
Heckman selection model. The findings show a teacher working more hours yields a negative effect
on students performance in both shifts. In addition, student studying is positive and statistically
significant in the morning shift. However, most of the effect of the morning shift on academic
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achievement is due to the difference in the characteristics of students. In other words, the random
assignment of students to the different schooling sessions may help to eliminate apparent average
difference in the performance scores.
The importance of this research contributes to the debate of public policies and, moreover, the
ways that government institutions address the consequences of the double-shift schooling system.
In the case of Mexico, the double-shift schooling provides a solution to issues related to scarce
resources and infrastructure limitations without creating inequalities in the quality of the education
students receive between the two sessions.