Can free secondary school change how siblings affect each other’s schooling?

Tanzania’s removal of secondary school fees reshaped not only access to education, but also the way siblings’ schooling outcomes were linked. In “Sibling Spillovers and Free Schooling” by João R. Ferreira and Wayne Aaron Sandholtz (2025), the authors look at Tanzania, where the government removed secondary school fees, and ask whether that changed how families supported their children’s education.

They compare younger siblings of students who just passed Tanzania’s Primary School Leaving Examination (PSLE), the qualifying exam for secondary school, with younger siblings of students who just missed the pass mark. By focusing on students right around this cut-off, the authors use the exam result as a near-random dividing line, rather than comparing school entry directly. Before fees were removed, one child’s success often hurt siblings, but after the reform that pattern disappeared.

Methodology & approach

The authors use a large set of Tanzanian school and exam records to study how one child’s school progress affects their siblings. Since the records do not directly identify families, they match students using surnames and location (as a proxy for siblings), creating a large sample of older-younger sibling pairs.

They then compare younger siblings of older students who were very close to passing the exam needed for secondary school: some just passed, and others just missed out. Because these students were so similar, the comparison helps isolate the effect of the older sibling’s success on the younger sibling’s schooling.

The authors also split the analysis into the periods before and after Tanzania removed public secondary school fees. This lets them see whether free secondary education changed how families supported different children within the same household. To strengthen this comparison, the authors also use variation across regions and over time to show that the policy itself drove this change.

What was found

Before free secondary education, if an older child passed the exam, younger siblings were less likely to continue to secondary school themselves. This is consistent with the fact that families were often forced to choose where to put their limited money and attention. After school fees were removed, the pattern flipped. Younger siblings became more likely to continue and achieved higher scores. The benefits were especially strong in areas where constraints were more binding and for students who had previously been lower performing. The paper also finds that the change was not mainly explained by siblings copying each other or by children switching schools.

Why it matters

The main message is that free secondary education did more than just help more students enrol. It also changed how families divided support among their children. In simple terms, when school stopped costing as much, families were less forced to “choose one child over another.” That seems to have made it easier for more children in the same family to stay in school. The research serves as an important reminder that education policy can affect not only the child directly targeted, but also brothers and sisters at home.

Written by Constança Costa MSc in Economics by Nova SBE and Member of the NOVAFRICA Student Group.