Transcript Using a Classroom Response System to Implement an Interactive

Implementing Interactive Lecture
Demonstrations with a Classroom
Response System
Paul Williams
Department of Physics
Austin Community College
[email protected]
Abstract
Classroom response systems (CRS) provide an excellent
tool for promoting active engagement in the Physics
classroom.(1) CRS’s many uses include eliciting
common non-Newtonian physics conceptions by asking
students to predict outcomes of experiments. This poster
will describe the author’s use of CRS to implement
Interactive Lecture Demonstrations (ILD’s). ILD’s present
a sequence of related demonstrations and have been
shown to be an effective way to promote active learning
of physics.(2) An ILD on Newton’s 3rd Law was adapted
from Sokoloff and Thornton (3) and a second ILD on
Conservation of Angular Momentum was developed by
the author. Results of various assessments will be
presented.
Interactive Lecture Demonstrations


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Developed by Sokoloff and Thornton
Present Demonstrations with a Learning
Cycle
Good tool for promoting active engagement
and for eliciting and confronting common
non-Newtonian conceptions
ILD Process
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Demonstration is described
Students predict outcome on their own
Small group discussion occurs and then students
predict outcome again
Predictions are obtained from students
Students record final prediction – Excellent
application of Clickers
Demonstration is carried out
Students Describe the Results
Comparable physical situations are elicited from
students
Sample ILD – Newton’s


rd
3
Law
Two force probes measure the forces
between objects for eight different situations
In each situation students were asked to
predict the relative magnitude and direction
of the forces between the objects
Sample ILD Task
A massive cart, the truck, is pushed towards a
light cart, the car, that initially isn’t moving.
How does the force exerted by the truck on
the car compare to the force exerted on the
car by the truck.
How do the magnitudes of the forces
compare? (BY)
1.
2.
3.
4.
The truck exerts a greater
force than the car
The car exerts a greater
force than the truck
The forces are equal
Cannot be determined
0%
1
0%
0%
2
3
0%
4
How do the directions of the forces
compare?
(BY)
1.
2.
3.
The directions are
the same
The directions are
opposite
Cannot be
determined
0%
1
0%
2
0%
3
Assessment Details
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Used Newton’s 3rd Law (N3L) ILD in lieu of lab activity on
N3L in General Physics I
ILD was given after lecture on N3L
Post test consisting of 10 Questions on N3L taken from
FMCE were given following all instruction on force
Also examined free response question on Newton’s 3rd
Law on Unit test
Gave print version of ILD to section of Engineering
Physics I
Looked at same 10 questions from FMCE pre/post
Results from Spring, 2006
N3L Subset of FMCE

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GP1 Mean Correct 9.5
EP1 5.8 pre, 7.3 post
FMCE N3L Subset
Frequency

16
14
12
10
8
6
4
2
0
EP1 Pre
EP1 Post
GP1 Post
1
2
3
4
5
6
7
Number Correct
8
9
10
Knowledge Transfer
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An open response question concerning
Newton’s 3rd Law was given on unit test
Did knowledge gained in ILD transfer to a
novel situation?
Spring, 2006 Unit Test Question: Ice
Skater pushes on wall, identify force that
accelerates the skater.
Identified Force
PHYS 1401
(N = 18)
10
Reaction force to
student pushing on wall
Student pushing on wall 5
Static Friction
Force between objects
PHYS 2425
(N = 13)
8
2
3
3
Summary of Knowledge Transfer
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Students had difficulty in identifying the
reaction force as the force that accelerated
the skater
A task was added to the ILD for students to
identify the reaction force as a force which
accelerates an object
Modified ILD was given in Summer, 2006
Session to Section of General Physics I
FMCE Post Test Results from Summer,
2006

Mean Correct: GPI = 7.8
N = 24
Newton's 3rd Law from FMCE
Frequency

16
14
12
10
8
6
4
2
0
1
2
3
4
5
6
7
Number Correct
8
9
10
Summer, 2006 Unit Test Question: Ice
Skater pushes on wall, identify force that
accelerates the skater.
Identified Force
Reaction force to student
pushing on wall
Student pushing on wall
PHYS 1401
(N = 23)
18
3
Static Friction
1
No force Identified
1
Conclusions
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Addition of task of identifying reaction force
as accelerating force seemed to improve
student performance on unit test item from
56% to 78%
Performance on drawing free body diagrams
and identifying action/reaction pairs as equal
in magnitude but opposite in direction
seemed largely unaffected
Conclusions (cont.)
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Performance on 10 question subset of FMCE
is comparable between clicker and pen and
paper versions of the ILD and is comparable
to published results
Plan – will give modified ILD to GPI section in
Fall 2006, to investigate if improvement on
performance of identifying reaction force as
force that accelerates an object persists
ILD on Conservation of Angular
Momentum
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Consists of 4 tasks on rotating stool, 2 tasks
with bicycle wheel gyroscope, and 2 tasks
combining rotating stool and bicycle wheel
gyroscope
Students were asked to predict effect of
changing either moment of inertia or angular
momentum of one part of system on
rotational motion of the system
Results
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Assessment consisted of test item on final
asking students to predict and explain effect
of rotational motion of student on a
frictionless rotating stool when arms are
extended
100% predicted that angular velocity would
decrease and 100% realized moment of
inertia increased but only 38% combined that
with conservation of angular momentum to
explain decrease of angular velocity
Conclusion
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ILD as currently written seems to effectively
instruct students in effect on rotational motion
due to changing moment of inertia but does
not seem to address importance of
conservation of angular momentum
Plan – Will modify ILD to include events on
rotating stool with an external torque such as
increasing angular velocity even though arms
are extended
References
1. Duncan, Douglas, Clickers in the Classroom,
Addison Wesley, 2005, pp. 35-38.
2. Sokoloff, D.R., and Thornton, R.K., "Using
interactive Lecture demonstrations to create an
active learning environment," The Physics Teacher,
35, 340-346, (1997)
3. Sokoloff, David R. and Thornton, Ronald K.,
Interactive Lecture Demonstrations, Wiley, 2004.