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Interview: Roy Pea
Excerpts from an interview with Roy Pea, Director of
the Stanford Center for Innovations in Learning, Stanford University
Discussion of "Building on What We Know
Cognitive Processing"
Cognitive processing refers to what the mind is doing as
it listens, as it comprehends, as it produces symbol systems of all kinds,
whether it is language, whether it is visualizations of different kinds
of knowledge. And the term processing is used by analogy to the
computer which processes information, does various transformations of
it to get to results. And a lot of the work in cognitive science
sought to understand how the mind worked by building computer models of
how the mind worked. And they made some pretty good progress in
creating programs that could play chess rather well and solve algebraic
equations and things of that nature. Whether they've in fact provided
an account of how the mind works, is quite up for grabs. But the
term cognitive processing has stuck as a way for thinking about the reasoning
and thinking that goes on and how it is that the structures and processes
of the mind work to reason, to remember, to retrieve information when
it's appropriate, to transfer it to a new situation, to form concepts,
and do many of the things that are integral to the learning enterprise.
And so cognitive processing is an important thing to think about and learn
about, both as a teacher, but also as a learner. I mean, it's important
to emphasize that young kids have pretty developed theories of cognitive
processing themselves. People that have studied even elementary
school children's understanding of memory, of language, of reasoning,
they're quite reflective about these things. They recognize that
when they're tired or distracted, they don't do as well, they don't remember
as much. So they're attentive to cognitive processing. What
teachers can help bring to the equation from the learning sciences is
much more attention to teasing out what their learners are thinking and
believing by having them represent that knowledge in conversations, in
pictures and in other modalities.
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How we process information is so variably influenced, it's
a miracle that we do as good a job as we do. We can be influenced
by the energy we have at a particular time of day, hunger, things that
are very common sense. Things that are less common sense, that teachers
can do something about, involve how are students already thinking about
the subject matter, that they're doing some cognitive processing about.
And for that, it turns out that the research tells us we don't listen
enough to how our students think. We don't give them an opportunity
to voice their beliefs, to draw pictures, to tell them what they think
about and what they see. And many adults are surprised when you
actually start to interrogate a child in the most positive sense, to understand
how they think and believe, to find that their thoughts are very curious
and unusual constructs. They might believe that a cloud really is
alive, like a person, as a Piaget taught us years ago. Or that a
moving tree is a living thing like a person. And these beliefs that
they have are important to understand for us to go building on in instruction.
So, prior conceptions, some call them misconceptions, we prefer to call
them prior conceptions, are one very significant influence, that work
in the learning sciences has helped reveal over the last number of years
and that I think teaching can really pay attention to.
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One of the highlights, and again work in the learning sciences,
look at representations. Both mental representations how
is it, is it in images or words or in other symbol systems that students
are thinking. So this we talk about as mental representation.
But every bit as important are external representations, inscriptions.
When someone writes something down, a written language, a picture, a diagram
of how things work with little arrows for flows and so forth, processes
of some kind or other, and, it can be of considerable aid for the teacher
to understand how the learner's thinking and to help advance that learner's
thinking to use these multiple representational forms. And they
have different trade-offs. And this is part of what a learner needs
to know. A graph may be wonderful for looking at a slope, but not
so good for other purposes. So, each of the representations that
we use for reasoning and for asking questions, has trade-offs affiliated
with it. There are certain things that it's good at and other things
that it misses and, and part of what we need to help learners do is to
understand the strengths of those representations, and when they're appropriately
used.
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Visualizations are, as Rudolph Arnheim tells us in his famous
book Visual Thinking, one of the more interesting inventions of
human kind. Of course written language is a form of visualization,
but usually we're talking about many other things and they range from
pictures of actual, unique situations to diagrams that represent a huge
class of situations. They also include maps, concept maps where
one can do concept mapping of the relations between concepts and something
new that one is learning. And one of the things that visualizations
do is they use vision to think. And so, that's one of the strategies
that humans have acquired to overcome their cognitive processing limitations.
They can only keep so much in memory at once. The magical number
is seven plus or minus two. And so they write things down in the
world to serve in some sense as cognitive aids for their thinking.
So as we go writing or drawing a diagram we can start to look at part/whole
relationships in a way that's very hard if we have to hold it all in memory.
So a diagram can in a single glance, show the relation between the parts
of the machine to the machine itself. McAuley's wonderful book,
How Things Work is one good example
of this and in the computer world, more and more effort is going into
creating visualization systems that can help students understand very
complicated global phenomena like, issues in the environment, global warming,
and changes of that kind.
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Visualizations can help students depicting their thinking
about a situation which might include the provision of an explanation.
This is how it works because. And what visualizations can do is
off-load from a pretty limited memory, not just in kids, but in adults,
some of the work. That is to say you can draw in a picture something
that you then no longer have to remember as you go building a complex
story. So, I could create a diagram that describes my day and all
the things that I do in it and what I need to do as part of a plan.
We do that all the time it's called a to-do list. So the
to-do list ends up being a visual organizer that helps solve a number
of problems of memory and thinking. And the same thing that makes
a to-do list useful for an adult, makes concept maps and other kinds of
visualizations useful for kids. It becomes a cognitive tool for
reasoning and for explaining and for communicating.
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Well, many of the same strengths that make visualizations
useful for reasoning and thinking are available as tools for the teacher,
as well. The rub there, or the catch, is that if the teacher only
uses these powerful visualizations to tell knowledge to students, they're
not going to get the opportunity to give students the power of these same
tools. So, I did some research work in a number of, well-known high
school classrooms some years ago on how geometrical optics is taught in
physics. And this is an 18th century science it's
nothing new, but it involves how does light interact with matter, like
a lens or a mirror, to form images. People have experiences of this
every day. And, diagrams are used to teach this subject matter.
But in these classrooms where students did very well on tests, very famous
schools actually, when they were asked to reason aloud at a chalkboard
later, and by drawing a picture, they were very poor and didn't reveal
much understanding. And the simple reason was that they had memorized
the formulas. They had memorized the diagrams they had seen the
teacher put on the board, instead of having some facility with using this
powerful visualization tool themselves. So if teachers only use
visualizations in a lecture mode and don't give the students an opportunity
to construct visualizations, they're missing a crucial learning and teaching
opportunity.
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So, visualizations provide a new window into thinking beyond
hearing students talk. So a student who might be less verbally oriented,
may be quite willing to draw a picture of how they're thinking about things
and to even label its parts in a way that can then become what we would
call a conversational prop for a learning conversation something
that can be pointed at, refined, talked about in a learning community
in which all of the kids in the classroom are creating visualizations.
And part of what's really interesting when a teacher does this, in virtually
any subject matter it can be math, science or humanities, social
science, social studies, language arts is that you find real differences
in the diagrams and the pictures that kids create. And part of that
is due to their having different beliefs. Some of it is due to their
having idiosyncratic conventions for representing the knowledge in, some
form of a visual representation. So this gives you opportunities
as a teacher for doing several things at once. One is to introduce
more canonical or typical forms of representing those ideas visually.
Another is, learning about potential problematic conceptions in the way
that the child is thinking as revealed through those pictures. And
the third opportunity is that it provides their peers with a model for
both appropriate ways of thinking in the domain and problematic ones.
So it has many, many opportunities in making thinking visible.
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The differences between novices and experts in any of the
fields in which cognitive scientists have studied them, from chess to
writing to mechanics to bartenders, all of these different areas are ones
in which experts tend to among other things that differentiate them from
novices, see the world differently. They see patterns in situations
that are typical problems in the area. So if you're a chess master,
a classic finding that has chess experts versus novices, look very quickly
at chess boards that are flashed with pieces that are in legal positions,
that is ones that could've actually happened in the game, and you find,
not surprisingly, that experts remember far more than novices do because
they can see what the meaning of the different chess pieces in that position
is, what possible states of play they could represent because they've
had huge experience, usually over 50,000 hours to become a chess expert.
But if you, interestingly enough, just scramble up the pieces and show
the novices and experts those same boards, there's no difference between
an expert and a novice. So it's not that experts have bigger memories.
The novices do. But they've come to chunk the world differently
and what they see. The same thing works for an expert teacher versus
a novice teacher. When they look in a classroom in the to and fro
of 25 to 30 kids all vying for attention and, in the context of some complex
piece of teaching, novice and expert teachers see very different things.
They see different opportunities. They see different problems arising.
Like a chess player, they're running ahead what are different scenarios.
If I do this thing with that child's question, what will happen to this
other group? And so part of what it means to bring the child novice
to being more of an expert in relation to, say mathematical problem solving,
involves looking at what are the aspects of skills and concepts that an
expert has and how can we help scaffold or support the learner to go building
those. And so some of the things that differentiate mathematics
experts from novices are, among other things, their facility with lots
of representational systems. They don't only use equations.
They will write. They will draw diagrams. They will use computer
programs. They will create graphs of different kinds for looking
at functions. They will even do data tables, again, depending on
what their purpose is. And so they have a meta-representational
capacity. That is, they know what representational systems there
are and what they're good for and pick them. They also manage their
mental work. They have a metacognitive capacity to think about the
time that's allotted, think about what they know and don't know and focus
their attention so if they go pursuing a process for a particular point
in time, they don't run it into the ground and run out of time.
They'll go to a certain point, see that it's not gonna work, and shift
course. And so, these are only some of the properties that differentiate
novices from experts. But, part of the process of helping students
become more expert involve modeling the kind of thinking that a more mature
problems solver in the domain does, giving students opportunities to pursue
that same kind of thinking aloud with support from the teacher and the
distributed experts in the classroom, because some of the kids may know
more than that particular child. And to, over time, fade that kind
of support, having seen what expert problem solving looks like, and supported
the student in trying to perform at a higher level and then, withdraw
the support and see to what extent they can move themselves along an expertise
continuum. This is, of course, at a level of abstraction, but I'm
sure you'll be playing that out in the series in the concrete examples.
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There are various visualization techniques that are used
heuristically. Now this is a word that is kind of, to mean rules
of thumb. Things that may be useful, not necessarily guaranteeing
a result which an algorithm does. So, heuristically, a matrix, or
a table is often really good at brainstorming, and highlighting gaps in
one's thinking. So, if you'd like to take an example, you might
have the faculty who teach your math courses, as rows, and the different
topics that are covered in the curricula being the columns, and you might
find from a process of curriculum mapping that low and behold, there are
some missing topics that you should have been treating in the curriculum
that you didn't. This ends up being a useful value of the matrix
for faculty work. Well it's not surprising that it could be useful
for kids as well. And, so in their case, you might want to, be using
matrices for planning different kinds of story outcomes in a story writing
task, or, science problem solving as well.
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[looking at the segment in "Building on What We Know
Cognitive Processing" that features Sandie Gilliam]
Part of what this teacher does that's extremely useful is
setting the problem solving context in a motivational one of human narrative
and drama. And that helps, attracts students' attention, probably
relates to situations they could imagine themselves in, as opposed to
being simple, dry, decontexturalized formula. She then gives them
the opportunity for reasoning quantitatively about their use of supplies
during their trip, water in particular. And so they then have the
opportunity to talk about what the shape of a graph would look like for
water availability at different times in the trip when they were
trying to conserve and a period where they don't know they're going to
get water, when they refill and so forth. And these issues of rate
of change of a quantity are important not just for mathematics, but in
physics and in a whole host of other subject areas. So, engaging
students' sense making around a narrative that then provides a kind of
a smart tool, a graph, for helping reasoning with, is really a powerful
strategy for bringing mathematical meaning into students' reasoning and
experience, even in what, in this case could easily be a social studies
problem where no mathematics might normally be done. So, she's doing
a lot of work here weaving together some historical work, so the students'
making sense of situation and mathematical representations.
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[looking at the segment in "Building on What We Know
Cognitive Processing" that features Fe MacLean]
So in Fe's class, she has the students classify animals,
with cards that represent those animals because she's really interested
in how these students think about the animals and on the basis of what
features do they categorize them into groups. To hook back to our
novice/expert distinction, a lot of the methodology there for distinguishing
novices from experts has them sorting, different problems into piles.
And experts tend to look at deep similarities, between problems situations,
say in physics, whereas novices tend to categorize based on surface features
of the similarity of, for example, the diagrams and the problems.
Are there things going downhill in both problems? Whereas at a deep
structural level in terms of Newton's Laws, that might not be, those things
might not be similar. So in this case she's trying to tease out
what are the student's categories? And then she does some work tapping
the distributed expertise of the group around what are the features for
thinking about these concepts? Why are these different, species
in one category rather than another? And she starts to get out what
are the properties, that for these kids help define those categories.
A very different approach would've been to just tell them the answer.
What are the categories as we scientists have defined them, which doesn't
give the students an opportunity to, on the one hand do their own thinking
about it, nor does it give the teacher an opportunity to learn what they're
already thinking. And, of course, it doesn't mean that their results
will be error-free. They may have concepts that need some work.
But the point is, she's engaged their thinking in a way that if she'd
only told them the answers, she would've engaged only their memory in
a way that after the course is over and their tests are done, they are
most likely to go back thinking the same way that they did before.
So, the opportunity of bringing out students' concepts and then building
them in a conversation in the moment, is the powerful idea in this scenario.
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