In 2009 Professor John Hattie published Visible Learning: A Synthesis of Over 800 Meta-Analyses Relating to Achievement. This aggregated the findings from 800 meta-analysis of 50,000 research studies, involving more that 150 million students - into what works best in improving student learning outcomes.
Since then Professor Hattie has continued to collect and aggregate meta-analyses to the Visible Learning database. His latest dataset synthesises 1,400 meta-analyses of 80,000 studies, involving more than 300 million students. This is the largest global research evidence-base into what actually works best in schools to improve learning. The findings are summarised below.
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