A randomized evaluation suggests that a program which provided official textbooks to randomly
selected rural Kenyan primary schools did not increase test scores for the average student. In
contrast, the previous literature suggests that textbook provision has a large impact on test scores.
Disaggregating the results by students’ initial academic achievement suggests a potential
explanation for the lack of an overall impact. Textbooks increased scores for students with high
initial academic achievement and increased the probability that the students who had made it to
the selective final year of primary school would go on to secondary school. However, students
with weaker academic backgrounds did not benefit from the textbooks. Many pupils could not
read the textbooks, which are written in English, most students’ third language. The results are
consistent with the hypothesis that the Kenyan education system and curricular materials are
oriented to the academically strongest students rather than to typical students. More generally,
many students may be left behind in societies that combine 1) a centralized, unified education
system; 2) the heterogeneity in student preparation associated with rapid expansion of education;
and 3) disproportionate elite power.