Countries across sub-Saharan Africa have made impressive progress towards achieving universal school enrolment over the past few decades. But schooling isn't the same as learning.
Recent studies reveal that children in this region learn remarkably little at school. For example, only one in five third-grade students in Kenya, Tanzania, and Uganda have second-grade literacy and numeracy skills, and less than one third of sixth-grade students in Southern and Eastern Africa can solve a simple subtraction problem.
This "learning crisis" means that sub-Saharan Africa is currently a long way from achieving quality education for all, which is one of the United Nations' Sustainable Development Goals for 2030. The low levels of skills also reduce students' labour market prospects, and dampen countries' economic growth.
Among the many potential causes of this crisis, one that's often mentioned is the lack of preparation of children who enter school. The primary curriculum is demanding and can be hard to follow for children without previous experience of learning in a classroom setting. Increasing enrolment in preschools, which prepare children for primary school, is therefore often seen as a promising policy for raising learning levels. Accordingly, preschool education is on the rise in sub-Saharan Africa, with enrolment doubling from 15% to 32% between 2000 and 2017.
But until recently, there has been little empirical evidence of preschools' effectiveness in boosting learning outcomes. Some observers even speculate that preschools might be doing more harm than good due to their narrow focus on teaching basic academic skills, which ignores children's need for social and emotional development.
In our research my co-authors, Sanna Ericsson and Fredrick M. Wamalwa, and I sought to close this gap. We investigated the long-term impacts of preschools on children's learning outcomes in Kenya and Tanzania. Our study employed new, large-scale data from the Uwezo initiative, which uses household surveys to measure school-aged children's literacy and numeracy skills in both countries.
Importantly for our purposes, the data included individual-level information on whether a child attended preschool before starting primary school. This allowed us to trace the effect of children's preschool attendance on their skills up to the age of 16. Mirroring the scope of the Uwezo surveys, our analysis covered more than half a million children aged between seven and 16 across Kenya and Tanzania.
We found that there are important long-term benefits from attending preschool. In particular, children who went to preschool were less likely to drop out of school and had higher levels of literacy and numeracy when reaching adolescence.
An important feature of our study is the focus on causal effects, rather than mere correlations. To illustrate the difference between these concepts, imagine two primary school children from different families, one of whom did go to preschool and one of whom did not. Now imagine that the former child has better literacy and numeracy skills. Preschool attendance and learning seem to go together, they're correlated.
This correlation could be due to many factors: for example, the family who sent their child to preschool might be richer and foster the child's education in other ways too, which could explain the better skills. In our research, we wanted to measure the improvements in learning that preschool education actually causes, not just those that could be due to other aspects of the family background, such as financial resources.
To overcome this challenge, we studied siblings - children who share exactly the same family background. By comparing the skills of siblings who did and did not attend preschool, we were able identify the causal effects.
Our results show that there are important long-term benefits from attending preschool. For example, 64% of all Tanzanian 13 to 16 year-olds master basic, second-grade literacy and numeracy skills. We found that going to preschool boosted this rate by 5%, a significant difference. Similarly, preschool education increased the share of 13-16 year-old Kenyans mastering these skills by 3%, compared to a baseline of 84%.
Our results also show that adolescents who attended preschool are more likely to still be enrolled in school. This effect is particularly pronounced in Tanzania, where enrolment at ages 13 to 16 is increased by 8%. This is a considerable improvement given that 12% of all children of those ages in our sample report to be out of school.
Finally, our analysis reveals that the improvements in skills and enrolment are larger for children from less-educated mothers. While we cannot pin down the exact reason for this difference, one potential explanation is that these mothers tend to be poorer and thus might have fewer age-appropriate learning materials at home.
Taken together, our findings suggest that policies that increase access to preschools can be an effective instrument to improve learning outcomes in sub-Saharan Africa, as they have already been in other parts of the world. As such, they would also bring countries closer to achieving the Sustainable Development Goal of quality education for all.
A further benefit of getting more children from poor families to enrol in preschool would be that this could help close the achievement gap between children from different family backgrounds. Recent evidence shows that the pass rate of children in financially secure households on the Uwezo literacy and numeracy tests is more than 20% above that of children in very poor households.
The latter children are also much less likely to attend preschool, even though our results suggest that they could particularly profit from attending. Making it easier for poor children to go to preschool could thus decrease the differences in learning outcomes compared to children from financially secure households.
Finally, one important question that we were unable to answer is what actually makes a good preschool. Our analysis found that preschools in their current form, with their focus on teaching academic skills, are beneficial for children. Improving the quality of teaching in preschools might well lead to further benefits, and should be an important issue on the agenda of both researchers and policymakers.