Illustrative MathematicsStandards for Mathematical Practice: Commentary and Elaborations for Grades K-5

Description: Explanations and examples of how the Standards for Mathematical Practice apply to Grades K-5. Elementary students start by using everyday language to express their mathematical ideas, realizing that they need to select words with clarity and specificity rather than saying, for example, "it works" without explaining what "it" means. When measuring, mathematically proficient elementary students use tools and strategies to minimize the introduction of error.