Even though Indigenous exclusion in education is well understood, there is a lack of comparable evidence across-regions on the extent of the learning gap and challenges faced by Indigenous students and, in turn, which policies may mitigate them. In this paper, I use the new PISA-D learning survey for seventh grade students and I first estimate the learning gap of Indigenous students in Guatemala, Paraguay, Senegal, and Zambia through quantile treatment effects and, then, I assess whether earlier literacy exposure in the mother-tongue language can help towards lessening achievement gaps for Indigenous students. After accounting for Indigenous and non-Indigenous students background differences, I found that the unexplained learning gap can be substantially reduced and turn out to be insignificant if Indigenous students had previous exposure to home language at primary school, especially for low achievers. Thus, school policies providing learning skills in the home language could be an important leveller when transition to the main language at later education stages, boosting equity in line with equity targets of the sustainable development agenda.

尽管教育中的土著排斥已为人们所熟知，但关于土著学生面临的学习差距和挑战的程度，以及哪些政策可能会减轻这些差距，缺乏跨地区的可比证据。在本文中，我使用针对七年级学生的新 PISA-D 学习调查，首先通过分位数处理效应估计危地马拉、巴拉圭、塞内加尔和赞比亚土著学生的学习差距，然后评估是否较早的识字暴露母语语言可以帮助减少土著学生的成绩差距。在考虑了土著和非土著学生的背景差异后，我发现，如果原住民学生之前在小学接触过母语，那么无法解释的学习差距可以大大减少，并且变得微不足道，尤其是对于成绩不佳的学生。因此，在教育后期过渡到主要语言时，提供母语学习技能的学校政策可能是一个重要的平衡器，根据可持续发展议程的公平目标促进公平。