International evidence shows that investing in high-quality early childhood programs can have large economic returns, especially for children from socially disadvantaged groups. In response, developing countries are looking to increase public investments in the early years, especially in early education programs. As they do so, one of the challenges policymakers face is deciding what to fund. After all, there are a wide range of opportunities for early childhood education that already exist in local settings such as playgroups and kindergartens. As a result, different children can often have very different early childhood education experiences on their way to primary school.
The inefficiency and inequity caused by age differences in testing is not news. On the contrary, it is a well-documented fact. The proposed solution to this problem is to age-adjust test scores. But the truth is, we are nowhere near to implementing such a solution.