A structural component with at least two side members has a support structure that includes a partition with multiple curved portions forming cells. The partition connects to the side members and extends between the side members at least partially along straight lines. The partition may extend along one or more straight lines from one side member to the other. One structural component is a container with a wall about the internal support structure. The container cells may be formed with a core structure. The core can include a permeable storage material and may be retained after formation, or may be removed. In some cases the container wall has generally planar surfaces, which may include surface undulations. Core structures are also provided for forming structural components. Formation can include casting a material about a core structure within a mold to form a partition extending between two or more sides.