Paper: The Limits of a “Great Buy”: What Rigorous Evidence Reveals about Teaching at the Right Level
Abstract
Teaching at the Right Level (TaRL), which targets instruction to students’ learning levels rather than grade level, has been widely promoted as a highly effective and cost-effective approach to improving foundational skills and has been classified as a “great buy” by the Global Education Evidence Advisory Panel (GEEAP). This paper provides a critical reassessment of the evidence underlying this classification, focusing on studies that employ rigorous causal identification strategies and evaluate conventional TaRL models at the primary school level. The findings show that TaRL can improve foundational literacy and numeracy, particularly for students who are furthest behind. However, impacts are heterogeneous and often modest, with a substantial number of null results. The largest effects are concentrated in high-intensity models implemented with close supervision, while results are weaker in system-embedded programmes. Evidence on cost-effectiveness is limited and uneven. Overall, the available evidence is not sufficiently consistent or robust to support broad claims of effectiveness and cost-effectiveness across contexts. Rather, it suggests that TaRL is not a uniformly effective solution, but an approach whose impacts depend critically on implementation conditions, calling for more cautious interpretation in policy and funding decisions.