Abstract: A wall panel system of the present invention includes a plurality of inter-connecting tongue-and-groove panels which are framed by top, bottom, and side channel members to form walls which may be easily erected and taken down. The bottom channel member has a back leg, a front leg, and a bottom surface extending between the back and front legs. The top channel member can either be an integral, one-piece assembly or a two-piece assembly. In the one piece assembly, the top channel member is substantially similar to the bottom channel member. The two piece top channel member includes a fixed member and a locking leg mountable to the fixed member. The fixed member includes a back leg, an upper surface, and a rearwardly facing groove in the upper surface. The locking leg includes a finger which is received in the groove. The locking leg can have either a single panel or have or a pair of spaced apart arms.