Students identify points, line segments, lines, rays, polygons, triangles, quadrilaterals, and common two-dimensional shapes, and classify them by attributes such as side lengths, vertices, right angles, parallel or perpendicular sides, and overlapping categories. They recognize angles as turns, identify and compare right, acute, and obtuse angles, identify and complete lines of symmetry, recognize congruence and translations, rotations, and reflections, and partition shapes into equal-area parts. Students identify common three-dimensional objects and their faces, edges, and vertices, distinguish solids from their two-dimensional faces, and relate familiar cubes, rectangular prisms, and simple prisms to informal nets.