Promoting and studying deep-level
discourse during large-lecture
introductory physics
Dedra Demaree and Sissi L. Li
Physics Department,
Oregon State University, Corvallis OR
Physics Education Research Conference, July 2010
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Introductory calculus-based physics
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Three term sequence with three 1-hour
lectures per week
200 students per lecture section, heavily
incorporating active-engagement
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Curricular model: Investigative Science
Learning Environment (ISLE):

ISLE goals: Building Scientific
Abilities Representing
information, conducting
experiments, thinking divergently,
collecting and analyzing data,
constructing, modifying and
applying relationships and
explanations, being able to
coordinate these abilities

ISLE Meta-Goals: scientific discourse, metacognition, evaluation,
brainstorming multiple explanations, reconciling different solutions,
understanding when models apply (assumptions), discussing openended situations…
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Pedagogical reform methods:

Peer Instruction (PI) and group work are used to facilitate
ISLE goals during lecture
Goal of helping
students build
sophisticated
discourse
Develop a classroom
community for the
practice of meta-goals
Reform success:
Normalized FCI gain

Fall 2008
0.40
Fall 2009
0.40
Provide opportunity for
students to make meaning in
class to build a shared
repertoire of knowledge
BUT, need effort to
help students practice
the meta-goals within
the classroom
community
Goals are supported by homework, lab write-ups, and exam
questions (students are asked to state assumptions, justify
the application of model, explain reasoning…)
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Using the Communities of Practice (CoP)
framework

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Focus on helping students belong to the classroom
community in order to participate in learning
opportunities
Ability to contribute to and negotiate practices of the
community supports more participation and more
central identities.
Having contributions accepted as valid and worthy
affirms identity of being a member in the CoP
Teacher is “Broker”: bridge between professional physics
community and classroom community, rather than a
dictator
Wenger, E. (1998). Communities of practice: learning, meaning, and
identity. Cambridge University Press.
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Set meta-goals and write classroom activities aimed at
supporting them
Teacher discusses subtleties of open-ended
problem solving through lecture
Teacher models
discourse via whole
class conversations
Teacher models
discourse via interacting
with groups during PI
Students adapt discourse
practices within groups
Post-class analysis of
researcher observations,
and student and teacher
dialogue
Are goals met? Refine process and
scaffold in new meta-goals
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Classroom community can be encouraged during
‘lecture mode’ where students justify reasoning and
provide explanations without direct prompting
Can you
explain
that more?
What is your
understanding so
far?
In lecture, a student interrupted with a
question. Instead of launching into
another explanation, teacher asked for
his existing knowledge. Teacher is
acting in the role of the broker, helping
the student practice dialoging in a
scientific fashion.
The student then explained their reasoning,
and a second student immediately
understood their viewpoint, and chimed in
with a great explanation for the first student.
The second student had held the same view
a few minutes prior and had just come to
understand my explanation and had made
sense of it himself using that ‘if then’
reasoning.
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Challenge student expectations to alter
classroom norms with open-ended, or
multiple answer voting questions:
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PI Questions to model reasoning and to
validate ideas brought up by students
Which of the following explanations were consistent with
our observation experiments?
1.
2.
3.
4.
5.
The motion is the vector sum of all interactions
The force of the hand on the ball is greater than the force of
the earth on the ball, therefore the ball doesn’t move
The force of the hand on the ball is equal to the force of the
earth on the ball, therefore the ball doesn’t move
If there is more force in one direction, the object will have a
change in motion in that direction
Interactions have the ability to cause motion if they are
unbalanced
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Encourage students to rely on their prior community
developed knowledge to address completely new situations
Prompt: “think about it in terms of 211 ideas”
(applying mechanics ideas from fall term to the
winter term course). Voting Question: An object
hangs motionless from a spring. When the object
is pulled down, the sum of the elastic potential
energy of the spring and the gravitational
potential energy of the object of the Earth
1. increase
Based on Newton’s 2nd law, predict what will happen to the
reading of the spring scale when the mass is accelerated
2. stays the same
upward (a>0), then moves at constant velocity, then is
accelerated (a<0) to a stop. JUSTIFY YOUR PREDICTION
3. decreases
WITH FORCE DIAGRAMS!!
http://paer.rutgers.edu/pt3/experiment.php?topicid=3&exptid=172
1.
2.
3.
4.
5.
The reading will be the same at all times
The reading will increase, stay steady above the ‘at rest’
reading, then decrease back to the ‘at rest’ reading once the
object has come to rest
The reading will increase, go back to the ‘at rest’ reading
then decrease before the object comes to a full stop
The reading will decrease, stay steady below the ‘at rest’
reading, then increase back to the ‘at rest’ reading once the
object has come to rest
The reading will decrease, go back to the ‘at rest’ reading
then increase before the object comes to a full stop
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Teacher provides opportunity for shared authority
with students while circulating among groups
One student in a group asked a question too
softly for the teacher to hear.
T: Hmm?
Teacher
listens but
does not
respond until
the group
members
have their
chance to
speak.
Authority to teacher, asking
for the ‘right answer’
Student taking authority to
express understanding
Student validating S2’s right to
answer in place of the teacher
Teacher taking authority but
also validating both students’
ideas and return meaning
making to the students with
question
S1: Will the bullet have a trajectory like
that or will it just go straight?
S2: The bullet’s gonna drop a little bit…
S1: Yeah.
T: It will drop a little bit. So you are both
right, the bullet’s gonna slow down
but does that tell us what’s going to
happen?
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Use research-based observations to refine
activities to better achieve goals
Group-work prompt: Observation experiment: make physical
representations for the following
◦ The motion of the ball with respect to the table
◦ The motion of the cart with respect to the table
◦ The motion of the ball with respect to the cart

From Instructor Journal: (Wed, Oct 15) Today I tried ISLE observation
and testing experiments … 2nd class tossed out magnetism idea - first
class didn't come up with any alternate explanations. emphasized
representation which gave away answer, did in part for discussion of
reference frames which was important. Better way - multiple
brainstorming, then represent motion then devise testing experiments
after we tested - then could get both effects. liked the discussion on
limits and assumptions - both classes brought up assumptions on their
own, liked tie in to projectile simulation to discuss effect of
assumptions.
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Prompts found useful to encourage
productive dialogue and engagement
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Encouraging discourse and acknowledging struggle: "Go
ahead and talk to your neighbors, this is not
particularly easy."
Encourage students to teach and value social learning: “I see
from the results that it would be helpful to talk to your
neighbor, so go ahead and do that.”
Encouraging re-thinking of classroom social norms: "If you
are not near a neighbor, just shout. It can get loud in here
that's fine with me.“
Leaving students responsible for though process: "Give it a
try. See what you think.“
Expecting students to immediately use methods just
modeled for them: “Give you a chance to think about
how to apply these things.”
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Evidence of students adapting discourse
 Context:

Skills and practices demonstrated:
◦ Part I: Origin choices, assumptions, interpreting
task/open-ended question, sense-making
◦ Part II: System choices, analysis of set-up, justifying
choices, checking if reasoning makes sense
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Part I
Speaker
Discourse
S3
S2
Ok so at the edge of the roof, that’s where it has its highest potential and lowest kinetic. [Reads] What do you
need to find your diagram? Write the math… [inaud] representation with your diagram… [looks to towards S1
and S2]
Um…
S1
So …
S2
We just need to define this…
S1
…the states. So initial is… exactly what it says, just after leaving the roof. [S2 writes]
S3
[to himself] Well initial and final would be the same… but…
S1
[to S2] And then you have to state the origin is… the ground.
S3
[to himself] … initial and final… potential and kinetic doesn’t have to be a different story.
S1
All potential…
S2
All potential is…
S4
At the top…
S1
You’re assuming it’s not rolling off with speed.
S3
It’s at the very edge so it’s not sliding off the roof, it’s just tipped over.
S1
Right. [turns face to nod and acknowledge S3’s comment]
S2
At the origin…
S3
Yeah.
S2
…height equals zero.
S3
So for afterwards it would have zero potential… lots of kinetic and in the beginning reverse that.
S2
The cat entering our system?
S3
Right.
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Part II
Speaker
Discourse
S3
Ok the system would be… the cat and the ground. [pause] Well the cat and the Earth obviously. And the roof is
pretty much…
S3
[turns to S1 who turns to face S3] Would the system be the… I know it’s the cat and Earth at least, but would
the… roof be part of the system or…
S1
S3
S1
It wouldn’t need to be.
Yeah…
Cause the only thing interacting is the cat with the ground, with the Earth due to gravity.
S3
S1
S3
Yeah.
That’s our only interaction. We’re going…
It’s pretty much just the position and place. [pause] Doesn’t add or take anything away from it, except just
gives it a position for the cat to be on.
S1
S3
S1
It is what gives the cat the initial potential energy.
Yeah.
Cause the cat got up there. That’s what it amounts to. If you get up there you’ve expended energy, you have
to gain that back to get back down.
S2
[S1 turns to look at S2’s notebook] We didn’t really write a mathematical representation, did we?
S3
[S1 turns back to face S3] Yeah. But technically though, if you expend the energy to go up and go back down…
you technically… physically, in physics you gain… it’s equal but when… biological sense, you don’t get it back.
S1
Right.
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Abstract

At Oregon State University, the introductory calculus-based physics
sequence utilizes social engagement as a learning tool. The
reformed curriculum is modeled after the Interactive Science
Learning Environment from Rutgers University, and makes use of
Peer Instruction as a pedagogical tool to facilitate
interactions. Over the past two years we have utilized a number of
techniques to understand how to facilitate activities that promote
productive discussion within the large lecture classroom. We
specifically seek student discussion that goes beyond agreement on
conceptual questions, encouraging deeper discussions such as what
assumptions are appropriate, or how different assumptions would
change the chosen answer to a given question. We have
quantitative analysis of engagement based on video data, qualitative
analysis of dialogue from audio data, and classroom observations by
an external researcher. In this session we share a subset of what
we have learned about how to engage students in deep-level
discussions during lecture.
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