This is a fun way to play, with the real world challenge of stacking cups adding an extra dimension. (gonintendo.com)
Plastic stacking cups Plastic cups hold up better under a baby's wrath than cardboard boxes, and they can be used in and out of the bathtub. (policygenius.com)
The deep sides keep stacked cups from falling over, and it's hefty enough to haul everything I need. (bostonmamas.com)