In 2001, researchers Robert Marzano, Debra Pickering, and Jane Pollock published "Classroom Instruction that Works," a work that identifies nine instructional strategies that are most likely to improve student achievement across all content areas and across all grade levels.

• Overview: A brief description of the nine strategies, including effect size of each strategy

• 8 Strategies that Marzano and Hattie Agree On: Robert Marzano and John Hattie have both reviewed research into what teaching strategies make the biggest difference to students’ results. While they used different methods and terminology, they agreed on these 8 powerful strategies.