Students identify and classify points, lines, rays, segments, angles, triangles, quadrilaterals, polygons, and solids using defining properties such as side lengths, angle measures, parallelism, perpendicularity, symmetry, and relationships among special quadrilaterals. They measure and construct angles, use complementary, supplementary, triangle, quadrilateral, and full-turn angle relationships to find unknown measures, and reason about congruence, informal similarity, dilations, and lines and rotational symmetry. Students represent and perform translations, reflections, and rotations on coordinate planes, construct nets of prisms and pyramids, and identify informal cross-sections of common solids.