Abstract: In a changeable marquee sign, a plurality of elongated corrugated sheet material racks are horizontally disposed in vertically spaced relation. The ridges of the corrugated shape form forward and rearwardly facing vertical grooves which cooperatively receive spaced-apart longitudinally extending teeth formed on opposing end edge surfaces of a plurality of sign character panels to prevent unauthorized movement of the panels relative to each other or to the plane of the sign. The several panels being chosen to impart a desired message.