Abstract: A novel presentation board has a body of molded plastic which forms a strong, hollow, lightweight unit with a projecting tray and grip on a front surface and a corresponding recesses on a rear surface so the units can be conveniently stacked. The front surface of the body bears an extruded track for insertion and replacement of a whiteboard or other writing surface. The whiteboard is secured at a top edge of the body by two metal pegs, sized and spaced apart to accept a prepunched pad of flip chart paper, that pass through the whiteboard into threaded inserts in the plastic body. The grip protrudes from a top edge of the whiteboard and is slidably mounted on the pegs. When slid into a lower position, the grip hides the pegs and locks the pad in position. A pair of U-shaped tubular metal legs can be slid into channels in a rear surface of the body. The channels are covered, at all but part of their lower ends, by cover plates. Grasping the lower leg ends allows one to slide the legs from the unit.

Abstract: A ring-based sheet retainer can be removably attached to a blackboard or a presentation board. At least two sheet retainers are attached to a support member that is an elongate planar member equipped with mechanical fasteners designed to engage a complementary structure on a presentation board or the like. Each sheet retainer comprises an ring and a ring closure. The ring has the form of flattened oval: straight midportions connected by semicircular end portions. There is a gap in the midportion of the ring whereby sheets are inserted into the ring. The ring closure is a straight hollow cylinder sized to slide over the straight midportion of a gaped side of the ring. The closure is attached to the support member with an end overhanging the edge of the support member so as to receive punched sheets when the ring is open. Sliding the ring into the closure opens the ring by revealing the gap at the overhanging end of the closure.