Abstract: A displayboard comprises sheets with a plastics foam core formed in situ between them. Edging strips having internal channels in which the edges of the board lie are mechanically connected directly to the sheets either by tongues that project out of the sheets into recesses in the sides of the channels or by the pressure of the foam core when being formed forcing parts of the sheets into the recesses. The edging strips have external channels serving auxiliary functions, e.g. securing the displayboard to wall brackets, securing a hinge joining a second displayboard, securing a pencil tray and carrying a pelmet containing a spring-loaded clamp for clamping papers against the edging strip.