a novel structural member , such as a tennis racket frame , having an unusually high strength to weight ratio is provided comprising an expanded foamed plastic core integrally bonded to a shell comprising at least one layer of resin coated unidirectionally oriented graphite fibers , the shell completely encasing the core at any transverse cross section of the structural member . the structural member is prepared by arranging within a mold cavity an outer shell comprising at least one sheet of resin coated unidirectionally oriented graphite fibers and a core comprising a foamable resin composition , sealing the mold cavity and activating the foamable resin composition to cause expansion and generate pressure within the mold cavity and thereby provide intimate bonding of the core to the shell .