Students identify, describe, sort, and compare two-dimensional shapes by attributes such as straight or curved sides, open or closed boundaries, sides, vertices, right angles, and symmetry, recognizing circles, triangles, quadrilaterals, squares, rectangles, pentagons, and hexagons in varied orientations. Students identify and build familiar three-dimensional objects, including cubes, rectangular prisms, cones, cylinders, and spheres, by recognizing faces, edges, vertices, curved surfaces, and the two-dimensional shapes of their flat faces. Students compose and decompose two- and three-dimensional figures from smaller shapes and partition rectangles or circles into two, three, or four equal parts described as halves, thirds, or fourths.