Within this context one can see how big of an effect CTE truly is Throughout his Visible Learning journey John Hattie has used the “barometer” to visualize the effect size of an influence on student achievement. It has also also been on the cover of several Visible Learning books. The effect size of is indicative of a small to medium effect (42) and a In his ground breaking study “Visible Learning” he ranked influences that are related to learning outcomes from very positive effects to very nega