The second feature to consider is the hole at the top of the apparatus. This feature was especially unique because it was not obvious where the sand went when a child poured it in the hole.
For some children, detecting what happened to something put in the top hole was a latent discovery. Because they were able to follow the sound of the rocks through the box, the children in the video clip below figured out where the rocks exited the box.
Disappearing rocks from Thomas Bedard on Vimeo.
There are a couple of things to note from this video. The first was the joy experienced by the children, especially the one on the left, of discovering exactly where the rocks went. Maybe the joy was heightened a bit because it was necessary for their eyes and ears to work together to follow the tumbling rocks through the box and out the bottom. There was also an additional aural component to this apparatus: the big rectangular box amplified the sound of the rocks tumbling down the long, narrow box. That component briefly fooled the child on the right when he heard the other child's rock tumble down and he looked inside the big rectangular box for it. (Did you catch that when you saw the video? I didn't see it the first time either. It took me several passes and slowing the video down before I saw the child look for the rock in the big rectangular box.)
One child even figured out a way to modify that top hole. He propped a minnow net over the hole and then poured sand through it.
That was just two features of the apparatus and just a few of the different explorations by the children. How many more features and how many more explorations are there in this one apparatus?
As you can see, there is no way I can call this a failure. I forgot that children will approach the apparatus like any found object that they find intriguing. They will enter into a unique dialogue with the apparatus, a dialogue based on a whole set of experiences and competencies, a dialogue informed by their interactions with the physical materials. I just forgot that once I have built something, it is no longer mine. It then belongs to the children to make it their own.