Learning outcomes in low- and middle-income countries (LMICs) are consistently low (World Bank, 2018), yet curriculum expectations remain much higher than the benchmarks most pupils have met. This indicates a misalignment between pupil performance and policymaker expectations, and it is usually regarded as one of the contributing factors to the ongoing learning crisis (Pritchett and Beatty, 2015; Rodriguez-Segura and Mbiti, 2022). In addition to low average learning levels across many LMICs, researchers have also documented considerable heterogeneity in learning outcomes within classrooms (Muralidharan et al., 2019). This heterogeneity makes it difficult to deliver instruction that reaches most or all pupils in these classrooms, as teachers can deliver more targeted and effective instruction when classes are more homogenous (Duflo et al., 2011). In this sense, all else being equal, a broader baseline distribution of performance will result in instruction that only reaches a smaller number of students.
Given these pedagogical challenges posed by within-class heterogeneity, the literature has been appropriately concerned about the issue of within-class heterogeneity. Yet, on a macro-level, policymakers face a similar challenge with within-system heterogeneity when they perform activities like designing and implementing curricula, developing mastery benchmarks, and writing textbooks. They typically need to select a narrow level of learning to cater to in each grade, and it is therefore unlikely that they will effectively meet the needs of all pupils. Hence, collectively, the existing literature has not focused as much on within-system heterogeneity of foundational learning; instead, it often focuses on either overall low learning outcomes (World Bank, 2018) or discusses within-class heterogeneity (Muralidharan et al., 2019).
The present study aims to (1) quantify the extent to which within-system heterogeneity is present in a sample of 246 public schools across Rwanda and how this is mapped in conjunction with these pupils’ respective pedagogical needs toward mastering foundational literacy and numeracy, and (2) implement a randomized controlled trial where, in the treatment group, pupils’ pedagogical needs in each school*grade pair in Primary 4-6 are diagnosed at the start of the school year. Their teachers are then provided with customized teacher guides for the full year on literacy and numeracy. The control condition receives the same material across the board, regardless of their specific school*grade level, closer to the median level in each grade across the system.