Students explore spatial relationships through the use of nonobjective, abstract, or representational forms, products, or structures. Instruction may include, but is not limited to, content in green or industrial design, sculpture, ceramics, or building arts. Processes and techniques for substitution include wheel-thrown clay, glaze formulation and application, or extruded, cast, draped, molded, laminated, or soft forms. Media may include, but are not limited to, clay, wood, metal, plaster, paper maché, and plastic with consideration of the workability, durability, cost, and toxicity of the media used. 3-D artists experiment with and manipulate space-producing devices, including overlapping, transparency, interpenetration, vertical and horizontal axis, inclined planes, disproportionate scale, fractional or abstracted representation, and spatial properties of the structural art elements. Craftsmanship and quality are reflected in the surface and structural qualities of the completed art forms. Students in the 3-D art studio focus on use of safety procedures for process, media, and techniques. Student artists use an art criticism process to evaluate, explain, and measure artistic growth in personal or group works.