The Art and Science of Lesson Design: Practical Approaches to Boosting Cognitive Rigor in the Classroom - Paperbackby John R. Walkup (Author), Stephan Squire (With) The Cognitive Rigor Matrix superposes two of the most common tools used in K 12 education: Bloom's Revised Taxonomy and Depth of Knowledge. This matrix has been adopted by numerous state departments of education and national organizations to evaluate the rigor of educational materials. The matrix also offers a powerful ability to help teachers plan and carry out standards based lessons that best