A shade assembly for a wagon having a collapsible shade frame that transitions between an assembled state for providing shade and a disassembled state for stowing. The shade frame has at least a pair of long rods each having a distal end and a mounting end removably mountable to a mounting holder on a frame of the wagon. The long rods each has a plurality of rod sections in the disassemble state, and the rod sections are removably connected end-to-end to form corresponding long rods arranged in a cross configuration to form a support frame in the assembled state. A canopy comprising a shade material is supported on the support frame of the shade frame in the assembled state. Under the weight of the canopy, the shade frame is cantilevered at the mounting ends of the long rods by the mounting holder.