Expandable work tray for a step stool or ladder

A step stool comprising

• a step stool frame including a front leg unit having at least one step supported above ground underlying the step stool and a rear leg unit coupled to the front leg unit to pivot from a closed storage position to an opened use position, and
• an expandable tray assembly coupled to the step stool frame, the expandable tray including a fixed tray panel secured to the step stool frame, a movable tray panel mounted for movement relative to the fixed tray panel from a collapsed position arranged above the fixed tray unit to an expanded position arranged adjacent to the fixed tray unit, and tray-motion control means for guiding movement of the movable tray panel from the collapsed position to the expanded position such that during motion a top surface of the movable try panel is maintained in an upwardly-facing orientation so that objects supported on the movable tray panel can remain in place during transition from the collapsed position to the expanded position,
• wherein the movable tray panel is shaped to define a first recess surrounded only by a first outermost sidewall and a second outermost sidewall opposite and parallel to the first outermost sidewall and a rearwardly-facing end wall, the fixed tray panel is formed to define a second recess surrounded by a third outermost sidewall and a forwardly-facing end wall and a fourth outermost sidewall opposite and parallel to the third outermost sidewall, the first and second recesses cooperate when the movable tray panel is in the expanded use position to provide a compartment surrounded on all sides by only the side walls and end walls of the movable tray panel and the fixed tray panel and without as wall dividing the first and second recesses to retain items placed therein, and at least a portion of the first outermost sidewall is aligned with and with the third outermost sidewall and at least a portion of the second outermost sidewall is aligned with the fourth outermost sidewall when the movable tray panel is in the expanded position.