A sphere is a perfectly round, symmetrical three-dimensional object with no edges or corners. Of all the shapes, a sphere has the smallest surface area for a given volume. Our Look Kool Math whiz compares the surface areas of a sphere, a cube, a square-based pyramid, and an octahedron that all have the same volume; conclusion: the sphere has the smallest surface area. The sphere in nature is the most efficient shape. Try this cool experiment with our Look Kool math whiz: make a tetrahedron with pipe cleaners, dip it twice into a soap bubble solution (1 part dish soap to 6 parts distilled water) and see the shape taken by soap film.