This leads to the fundamental question:
How can we help each and every child find this simplicity, in a way that works,
for them?
Lesson study focuses on the whole class activity. Yet within any class each child
brings differing levels of knowledge into that class, related not only to what they have
experienced before, but how they have made connections between the ideas and how
they have found their own level of simplicity in being able to think about what they
know.
To see simplicity in the complication of detail requires the making of connections
between ideas and focusing on essentials in such a way that these simple essentials
become generating principles for the whole structure.
In my APEC presentation in Tokyo (Tall 2006), I sought this simplicity in the way that
we humans naturally develop mathematical ideas supported by the shared experiences
of previous generations. I presented a framework with three distinct worlds of
mathematical development, two of which dominate development in school and the third
evolves to be the formal framework of mathematical research. The two encountered in
school are based on (conceptual) embodiment and (proceptual) symbolism. I described
these technical terms in more detail in Tall (2006) and in a range of other recent
papers on my website (www.davidtall.com/papers).