The Visible Learning Research

The world's largest evidence base on what works best in schools to accelerate student learning


Professor John Hattie

John Hattie of the University of Melbourne, Australia, has long researched performance indicators and evaluation in education. His research, Visible Learning, is the culmination of more than 25 years of examining and synthesizing more than 1,700 meta-analyses comprising more than 100,000 studies involving 300 million students around the world.

Hattie wanted to understand which variables were the most important. Although “almost everything we do improves learning,” why not prioritize the ones that will have the greatest effect?

Hattie set about calculating a score or “effect size” for each, according to its bearing on student learning and taking into account such aspects as its cost to implement. The average effect size was 0.4, a marker that represented a year’s growth per year of schooling for a student. Anything above 0.4 would have a greater positive effect on student learning.

Together with John Hattie, Corwin's Visible Learning+ professional learning enables schools and districts around the world to effectively implement the core findings of John Hattie's research.


Research at your fingertips

Visible Learning MetaXThe power of the Visible Learning research lies in helping educators understand, measure, and evaluate the impact they can have on student growth and achievement. 

Visible Learning Metax offers unparalleled access to the most up-to-date Visible Learning research, interpretations, and analyses — making it possible to understand the research and adapt it to your particular context. Powered by John Hattie’s groundbreaking Visible Learning research, Metax aims to help close the gap between the research of what works best for student achievement.

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