This is a Toonerville Trolly toy based on the classic comic strip....
Both the old Smithsonian "castle" and this, the history museum, had little cases like this one with fascinating objects representing the famed collections that the institute has maintained. However, the history museum itself was, for me, was a huge dissapointment with its many digitally enlarged and reproduced 'educational' rooms taking up most of the space and very little of the actual collection.