"the kindergartners saw the logic of breaking things into tenths and being able to see and understand how we were looking at smaller and smaller parts. When a couple of them started reading dimensions to the hundredth place with the decimal accurately placed, it really got me to thinking about how we teach." The answer he believes, is that "thinking spatially is that missing piece."Thinking spatially is indeed a missing piece, and one that wood shops and craft programs of all kinds offered at one time in American education. Remove the hands, you have removed all opportunities for concrete engagement.
We expect kids to be engaged in learning without ever having given them any concrete attachment to the subject material. Does it work? Think for yourself how things work in your own life. You may have lots of interests, some idle, some active. How did you get started on the ones that are most compelling? I suspect it had something to do with your hands.