A molded structural panel with substantially parallel major surfaces includes integrally formed thin thermosetting resin high density outer sections. Less dense thermosetting resin foam intermediate sections extend inwardly from the outer sections with the density of the intermediate sections decreasing substantially uniformly with increased spacing from the outer sections. A thin thermosetting resin high density central section is located between the intermediate sections. The high density outer sections are in a stressed state from the pressure of the foam intermediate sections thereon. Also, a method for molding the panel.Rotational molding apparatus includes a chemical supplying portion, a chemical mixing portion, a mold portion, a mold supporting portion, a mixture delivery portion and a control portion. The chemical mixing portion includes a tubular member disposed in a substantially horizontal orientation with a plurality of spaced angled deflector sections. The mold portion includes a pair of spacially connected substantially parallel frame sections. The mold supporting portion includes spaced upstanding sections with rotating clamping members selectively engageable with opposite edges of the mold portion. The mixture delivery portion includes a translatable elongated hollow probe member that is selectively connected with the tubular member.