books.google.ca - This unique and ground-breaking book is the result of 15 years research and synthesises over 800 meta-analyses on the influences on achievement in school-aged students. It builds a story about the power of teachers, feedback, and a model of learning and understanding. The research involves many millions...http://books.google.ca/books/about/Visible_Learning.html?id=c2GbhdNoQX8C&q=grade&utm_source=gb-gplus-shareVisible Learning
