Constructing Scientific Explanations

—
In this video Paul Andersen shows you how you can use modeling to have your students construct explanations in the science classroom.
—

—

Transcript Provided by YouTube:

00:00
hi it’s Paul Andersen and in this video
00:02
I want to dig more deeply into
00:03
constructing scientific explanations
00:05
this has always been a huge part of
00:07
science but we want to be a part of
00:08
science classrooms as well we want kids
00:11
constructing their own explanations for
00:13
how the world works or why events occur
00:15
a really good way to do that is through
00:17
modeling instruction where students
00:18
create their own and construct their own
00:20
cognitive models or mathematical or
00:22
computational models it’s basically how
00:24
the world works now remember this video
00:26
is part of a series of videos I’m doing
00:29
on scientific inquiry I’ve got a bunch
00:30
of resources inquiry cards and graphic
00:33
organizers that go along with this but
00:34
when I was starting to work on
00:36
constructing explanations I had a hard
00:38
time delineating between an explanation
00:39
and an argument what is an explanation
00:42
an explanation explains how it works and
00:45
what I mean by it is the natural world
00:47
versus a science argument what explains
00:49
how you know what was helpful as I was
00:52
going through this was an article I read
00:54
by Osborn and Patterson I’ll put a link
00:56
in the description down below
00:57
essentially if you’re using evidence to
00:59
construct a claim or to create a claim
01:02
that somewhat in doubt then you’re
01:04
probably doing an argument and we’ll
01:05
talk about that in a later video when
01:07
you’re coming up with an explanation
01:09
you’re determining a cause and a
01:11
mechanism for an effect that is not in
01:13
doubt what does that mean well every
01:16
explanation is going to have an
01:18
explanation
01:22
so if we look at these three questions
01:24
why did the dinosaurs die out why do we
01:26
have seasons and why do things fall each
01:28
of them have an explanation which is
01:30
that thing we’re trying to explain if we
01:33
move those over to the right we find
01:34
that those are the effects and those are
01:37
not in doubt no one doubts that we have
01:40
seasons or things fall or if we ignore
01:42
Birds that dinosaurs died out what’s an
01:45
explanation going to do it’s going to
01:47
determine the cause and the mechanism
01:49
for these effects so if we look at
01:51
dinosaurs for example you’ve probably
01:53
heard a lot of people think there was a
01:54
massive meteorite impact that through
01:56
atmospheric dust into the atmosphere
01:58
temperature dropped and then the
01:59
dinosaurs died out and so as we create
02:02
that explanation it brings increased
02:04
understanding to how the world works and
02:06
so what explanations do is they really
02:09
answer those questions of why why is the
02:12
sky blue
02:13
or how to unbalance forces cause motion
02:16
now I found when kids are doing
02:18
explanations a graphic organizer with
02:20
cause mechanism and effect is really
02:22
helpful so let’s say we’re looking at
02:24
the phenomena of antibiotic resistance
02:26
so these bacteria in this petri dish are
02:29
resistant to these three antibiotics so
02:32
that’s going to be the phenomena so we
02:33
could put that in the effect you always
02:35
put the effect there first and then
02:36
we’re going to work backwards to
02:38
determine what’s the cause and what’s
02:40
the mechanism now if I were to give you
02:41
the answer you’ve probably heard this
02:42
before antibiotic resistance is probably
02:46
due to overuse and under use of
02:47
antibiotics what’s the mechanism that’s
02:50
going to be natural selection and so
02:52
what do we have here we have a coherent
02:54
explanation now you might say I’ve been
02:56
doing explanations forever as a science
02:59
teacher I was too but I was probably
03:01
providing those explanations just like I
03:03
did a second ago I gave you an
03:05
explanation and what we want kids doing
03:08
with this practice is we want them
03:09
constructing their own explanations and
03:12
this is really hard you as a teacher
03:13
have to move from the explainer the sage
03:16
on the stage to more of a guide on the
03:18
side as the students construct their own
03:20
models that construct their own
03:22
explanations over time now this is based
03:24
on that constructivist idea of learning
03:26
that we all have an understanding of how
03:28
the world works and then we have to
03:29
construct a more coherent understanding
03:31
now when students are doing this I’ve
03:33
found what’s helpful is giving them a
03:35
cross-cutting concept cause and effect
03:37
that helps them kind of organize their
03:39
explanations and also a fairly recent
03:43
new pedagogical tool visual thinking is
03:45
helpful as well we want kids visually
03:47
showing us their models what they’re
03:49
thinking
03:50
once that’s outside of their brain on a
03:52
piece of paper on a whiteboard so we can
03:54
look at it then we can start to build
03:55
explanations over a time if we look at a
03:58
rubric for what makes a good explanation
04:00
it should always have a cause and then
04:02
if we’re looking at the model that
04:04
you’re trying to explain you should
04:05
identify the relevant components of the
04:07
model and then how do those connections
04:09
explain describe and predict these would
04:12
be the elements of a good explanatory
04:14
model now if it’s an advanced model you
04:16
may add numbers to that mathematically
04:19
representing some of the elements of
04:20
that model or use computational modeling
04:22
I’ve gone into all of this a video I
04:25
made
04:25
modeling instruction I’ll put a link in
04:27
the description down below but if you’re
04:28
just getting started this is a graphic
04:31
organizer that I use with students on
04:33
the left side
04:34
I’ve got also a teacher version of it so
04:37
you could look at like what I think are
04:38
the big elements that you should use as
04:40
a teacher but what we essentially want
04:42
them doing is telling us what they think
04:44
and so let’s say we’re looking at these
04:46
birds that are dipping as kids are just
04:48
getting started constructing these
04:49
explanatory models you probably want to
04:51
give them the question that they’re
04:52
trying to answer in this case what
04:54
causes the birds to keep tipping now we
04:56
want them to create a model you can
04:58
think of this as an explanation
05:00
explanatory model if you want to call it
05:02
an explanatory hypothesis it’s
05:04
essentially what they’re thinking at
05:06
this point now it’s important that since
05:08
they’re going to be drawing a model or a
05:09
system model that you curate the
05:11
important parts that you want in that
05:13
model so in this case if we’re looking
05:14
at this dipping bird I might tell
05:16
students that I want the bird included
05:17
in the model that cup that they’re
05:19
dipping into and maybe the surroundings
05:21
are important as well and then you want
05:23
to define the system that you want them
05:25
to create a model for define the
05:27
boundary in space and time lots of times
05:29
when kids are creating a model to just
05:31
draw a diagram or a picture which has no
05:33
explanation in it at all and so I would
05:35
say I want you to draw the bird in an
05:37
upright position and then a down
05:39
position so I can understand what you’re
05:40
thinking now we let the kids go we let
05:43
them create an explanatory model this is
05:45
an example of what that might look like
05:47
the student believes that what’s causing
05:49
those birds to dip is gas pressure or
05:52
this would be another explanatory model
05:53
maybe they believe it has to do with
05:55
density changes within the bird or
05:57
capillary action is a very common kind
06:00
of a system model when we’re looking at
06:02
an explanation for the bird but you also
06:04
want to have a spot where they tell me
06:05
what they’re thinking what’s your
06:07
explanation or what’s your cause I want
06:10
you to write that out so I understand
06:11
what you’re thinking other common
06:13
explanations if we’re looking at this
06:15
might be momentum is causing it to occur
06:17
or that we’ve got a temperature change
06:19
that causes it occur and so now you as a
06:21
teacher know what all the explanations
06:23
are in the class and the next step is to
06:26
test those models to test those
06:28
explanations out so if we look at where
06:30
this fits in this whole idea of inquiry
06:32
we start with a phenomena we use
06:34
questions to develop a lot of
06:36
explanations or you could call those
06:37
models
06:38
what we’re thinking but now we’re going
06:40
to systematically top test each of those
06:42
that’s why we do scientific
06:44
investigations some of those models will
06:46
fall apart some of those will have
06:48
elements that are we can kind of combine
06:50
into a shared classroom model of what
06:53
we’re all thinking and this is how you
06:54
can use inquiry in the classroom to
06:56
construct models as we’re all working
06:58
together and it also builds that sense
07:00
of I’m invested if a student is testing
07:03
out the models that’s based on what they
07:05
actually believe if let me give you an
07:07
example of this I was using this
07:08
phenomena as I was working with some
07:10
teachers at American Community School in
07:12
Amman so this was a fourth grade
07:14
classroom and then their teacher Jay
07:16
Cohen’s what he did is create a driving
07:18
question board where you put all of
07:20
their questions up he then put all of
07:22
their models up and then the students
07:24
are systematically going through and
07:26
doing investigations to test those
07:27
explanations to see which ones are wrong
07:30
and which ones are right nice thing
07:31
about science is there’s going to be one
07:33
reason for why this occurs and so we can
07:36
all work together to find that one
07:37
explanation
07:38
so that’s constructing scientific
07:40
explanations it’s what scientists have