The Effect of Multimodal Delivery of
Macroscopic and Particulate Level
Visualizations on Understanding
Chemical and Physical Changes
Barbara L. Gonzalez, Ph.D.
Biennial Conference on Chemical Education
Purdue University
West Lafayette, IN
July 31, 2006
California State University Fullerton
Department of Chemistry and Biochemistry
Visualization
•
Visual-Spatial
– Ability to mentally manipulate images in
three dimensions
•
•
(Coleman and Gotch, 1998)
Spatial visualization
– Ability to recognize, retain and recall an
object when it or parts of it are moved
•
Spatial orientation
– Ability to remain unconfused by
changes in the orientation of an object
•
•
(Bodner and Guay, 1997)
Imagery
–
–
Ability to elicit a visual representation of
a mental model
(Gabel,1999; Mathewson, 1999)
Visualization and Chemistry
• Visual-spatial skills develop from birth and
improve with practice
– (Lord, 1985; Kosslyn, Margolin, Barrett,
Goldknopf and Daly, 1990)
• Spatial-perceptual skills are related to
performance in a chemistry course and
males tend to have better skills in subjects
such as science
– (Bodner and Domin, in press; Carter, LaRussa,
and Bodner, 1987; Coleman and Gotch, 1998)
Understanding Changes in Matter
• Knowledge is constructed is accordance with
cognitive development and social interaction
– (Ginsberg and Oper, 1988; Vygotsky, 1969, 1978)
• Physical and chemical changes poorly
understood by learners of all ages and
backgrounds
– (Ahtee and Verjola, 1998; Herron, 1993; Johnson, et al.,
2000; Solsana, et al., 2003)
• Changes in matter in national and state
standards as early as elementary school
– (NRC, 1996; California Department of Education, 1990)
Developmental Patterns in
Understanding Chemical Change
• Acceptance
– The way nature behaves
• Displacement of matter
– Change is result of matter moving to a new place
• Modification
– Original substance is in a new form
• Transmutation
– Original substance is transformed into a new substance
• Chemical interaction
– New substance is result of dissociation and recombination
of atoms and molecules
– (Driver, et al., 1985, p.168)
Sample
• 245 students
• Two Institutional Levels
– Two Universities
• General Chemistry Laboratory
• Pre-service Elementary Teachers
– One Middle School
• Sixth grade science
• Two classes
• Science lessons taught by one
teacher
• 2002-2005
Design of Studies
TREATMENT
Institution
University
Course
Control Still Motion Mixed
Pre-Service K 74 28 13
18
8 Teachers
Science M ajors
Middle School Sixth Grade
TOTAL
22
22
33
15
9
11
129
65
22
29
Assessment
Subjects
PCA Pre-Test
N = 133
PCA Post-Test
PCA Pre-Test
N = 44
PCA Post-Test
PCA Pre-Test
N = 68
PCA Post-Test
N = 245
Research Questions
• Is there a significant difference in the ability to distinguish
between physical and chemical changes between
students who complete a visualization activity and those
who receive traditional instruction, as measured by mean
scores on PCA
— By treatment?
— By institution?
— By course?
• Is there a difference in the frequency of common
misconceptions that appear in written explanations of
physical and chemical changes
PCA
• Physical-Chemical
Change Assessment
– Ten items, two-tier,
multiple choice and
written explanation
– Four types of
representations
•
•
•
•
Macroscopic
Particulate
Symbolic
Visual
Which of the following best
represents a physical change?
A.
B.
Explain why it represents a
physical change.
PC Activity
• Four modes
– Control
– Still
– Animated
– Mixed
• Equal number of representations
– Macroscopic and particulate
– Physical and chemical
Macroscopic Level Animated
Click box to play movie
MP21
Particulate Level Still
+
SC13
PCA Results Entire Sample
mean score(out of 10)
PCA pre-test & post-test mean per
treatment group(entire sample)
10
9
8
7
6
5
4
3
2
1
0
control
still
animated
Treatments
pre-test
post-test
mixed
PCA Gain Factors By Course
PCA Ga in Fact or Me a n s By Cou rs e
1 .0
.9
Me a n PCA Ga in Fa ct or
.8
.7
.6
.5
.4
.3
.2
.1
0 .0
Mid d le Scho o l
Pre Ser vice Te ach e rs
Co urs e
(F = 3.31, df = 2, p  0.05)
Scien ce Majo r s
Middle School PCA Results
mean score
PCA pre -te st & post-te st me ans pe r
tre atme nt group in middle school stude nts
10
9
8
7
6
5
4
3
2
1
0
control
still
Animated
Tre atme nt
pre-test
(F=6.1, df=1, p<0.05)
post-test
mixed
Science Major PCA Results
Mean PCA Gain Factor
P C A M e a n G a in F a c to r b y T re a tm e n t fo r
S c ie n c e M a jo rs
1 .0 0
0 .9 0
0 .8 0
0 .7 0
0 .6 0
0 .5 0
0 .4 0
0 .3 0
0 .2 0
0 .1 0
0 .0 0
C o n tr o l
V is u a liza tio n
Tre a tm e n t
( t = 1 2 .7 2 , d f = 1 , p < 0 .0 5 )
Science majors who completed the still mode PC
Activity earned mean PCA gain factor scores that
were significantly higher than the control group
Middle School Explanations
PCA Explanation Code L, Middle School
100.0
% Frequency
80.0
60.0
40.0
20.0
0.0
1
2
3
4
5
6
7
Question Number
Pre Test
8
9
10
Post Test
Explanations do not demonstrate rich conceptual understanding
Quality of explanations improve with instruction
Findings
• Trend toward improvement in PCA scores for groups that
receive instruction that involves visualization at
macroscopic and particulate levels
– Pre-Service Teachers and Science Majors earn similar PCA gain
factor scores greater than MS
– Significant difference in all post test scores for middle school
learners who receive instruction that involves visualization
– Science majors who receive still mode visualization instruction
earn significantly greater mean gain factor scores on PCA
• Explanations improve with instruction for all groups
Implications
• Learners would benefit from actively engaging in real
examples as well as visual representations of physical
and chemical changes at the macroscopic and
particulate levels
• Because instruction on physical and chemical change
that involves visualizations led to a significant increase in
mean PCA gain factor scores for middle school students,
early and frequent exposure to is recommended
• Science and non-science majors need practice in
explaining and representing physical and chemical
changes at the macroscopic and particulate levels
Acknowledgments
National Science Foundation
CAREER REC-0133989
Dr. Ingrid Martorell
Azin Barzin
Maile Bay
Cindy Nguyen
Dionne Nguyen
Adriana Park
Chanda Strom
Di Trang
CSUF
CSUF
UCSB
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