Dr. Peter Liljedahl is a Professor of Mathematics Education in the Faculty of Education at Simon Fraser University and author of the best-selling book, Building Thinking Classrooms in Mathematics (Grades K-12): 14 Teaching Practices for Enhancing Learning. Peter is a former high school mathematics teacher who has kept his research interest and activities close to the classroom. He consults regularly with teachers, schools, school districts, and ministries of education on issues of teaching and learning, problem solving, assessment, numeracy, and building thinking classrooms.