Students relate physical materials, pictures, and diagrams to mathematical ideas.
Students recognize, describe, extend and create a wide variety of patterns. Students learn that mathematics is the study of many kinds of patterns, including numbers and shapes and operations on them. Sometimes patterns are studied because they help to explain how the world worked or how to solve practical problems, sometimes because they are interesting in themselves. Students learn that many objects can be described in terms of simple plane figures and solids. Shapes can be compared in terms of concepts such as parallel and perpendicular, congruence and similarity, and symmetry.