I spent a lot of time building and rebuilding this thing this weekend. The marble run can whip Oscar and Phoebe into a frenzy like no other toy in the house. They fight over nothing as fiercely as they do the marbles that come shooting out of those little holes. And nothing crumbles to the ground quite as satisfactorily or as often as the marble run does. I took this photo in disbelief because they actually left it standing on their way to bed. A marble run miracle.