Hattie’s meta-mata analysis that culminated in the publication of his most influential work of Visible Learning (2009), and later updated to include more studies, has been hailed as the “holy grail” for educators and education leaders around the world. In particular, his effect size of instructional practice interventions has had the lion’s share of his work. Hattie considered that if schools set the effect size at 0 then “virtually everything works, and so we need to shift the question from “ what works in education” to “what works best in education”. Hattie’s meta-meta analysis of more than 800 meta-analyses studies comprising 50,000 studies (later included more 1500 meta-analyses) revealed that the baseline of the effect size that schools should start from is not 0 but 0.4, termed as the “hinge point”. In other words, for medium to large effect sizes on student achievement, the effect size of an instructional practice should be o.4 and above. This does not mean that we n...
Reflections about and critique amongst life, and beyond, in the 21st century.