Journal of Science Education and Technology, Vol. 7, No. 4, 1998
A Longitudinal Study of Physics Students' Conceptions
on Energy in Pre-Service Training for High School
Teachers
Ricardo Trumper1
How physics students teachers' understanding of energy develops during their pre-service
high school teacher university program? How do their physics and Didactics courses influence
their energy conceptions? Do university physics students in pre-service training to be highschool teachers finally hold correct scientific views that will eventually allow them to plan
and implement instructional strategies that, in turn, will lead their future high school students
to achieve a scientific concept of energy? The results of a longitudinal study dealing with
this issues will be discussed in this manuscript. The energy conceptions of the Physics students
were analyzed by means of a two-part written questionnaire that was presented to the same
group on their first day of class for four years running. The most important findings of this
study can be summarized as follows. Despite their pre-service training, future physics high
school teachers: Hold a number of different alternative conceptual frameworks when describing physical situations, instead or besides the accepted scientific concept. Mostly think
that energy is a concrete entity and not an abstract idea. Mostly do not accept the idea of
energy degradation. Mostly confuse the concepts of energy and force.
KEY WORDS: Longitudinal study; physics students; energy conceptions.
In senior High Schools the compulsory subjects
are Optics, Mechanics and Electromagnetism and
there are also a series of elective subjects like Modern Physics, Relativity, Rigid Body, Alternate Current and so on.
INTRODUCTION
In junior high schools in Israel, the subjects of
Physics and Chemistry are being taught together according to the Curriculum of Physics and Chemistry
(1989) published by the Ministry of Education:
1. In 7th Grade the main subject taught is the
Particulate Nature of Matter;
2. In 8th Grade there are two main subjects:
a) Heat and Temperature and b) Chemistry
and Electricity;
3. In 9th Grade there are also two main subjects: a) Mass, Force and Weight and b)
Transformation and Conservation of Energy.
STUDENTS' CONCEPTIONS ABOUT ENERGY
The results of a great deal of research have
shown that, prior to any formal instruction in physics,
students hold incorrect conceptions about physics
concepts in general, and about the energy concept
in particular. Gilbert and Watts (1983) have summarized the general conclusions that can be derived
from these studies as follows: (a) energy is to do with
living and moving things, (b) energy makes things
work, and (c) energy changes from one form to another. This last framework has raised some contro-
1Correspondence
should be addressed to Ricardo Trumper, Oranim, School of Education of the Kibbutz Movement, Haifa University, Israel. Kibbutz Hahoterim, Doar Na Hof Hacarmel
30870, Israel. e-mail: R.Trumper@uvm.haifa.ac.il
311
1059-0145/98/1200-0311$15.00/0© 1998 Plenum Publishing Corporation
312
Trumper
versy since it is one that is sometimes explicitly
taught (Schmid, 1982). It is a view that sees energy
as traveling through machines and wires and changing appearances at different points.
Watts (1983) presented an exhaustive list of the
most popular and persistent students' alternative
conceptual frameworks abut energy, which was substantiated by Gilbert and Pope (1986):
framework, (b) the "cause" framework: energy causes things to happen, and (c) a
broadened "product" framework: energy is
the product of a certain process or processes.
2. After studying Physics, students generally
continue to adhere to the same alternative
frameworks held prior to formal study.
1. Anthropocentric: energy is associated with
human beings;
2. Depository: some objects have energy and
expend it;
3. Ingredient: energy is a dormant ingredient
within objects, released by a trigger;
4. Activity: energy is an obvious activity;
5. Product: energy is a by-product of a situation;
6. Functional: energy is seen as a very general
kind of fuel associated with making life comfortable;
7. Flow-transfer: energy is seen as type of fluid
transferred in certain processes.
In teaching the energy concept in the second
part of the study (Trumper, 1991), those students'
pervasive alternative frameworks were taken into account. The conceptual change strategies implemented in the study were based on the "cause" and
"product" frameworks that helped students build the
accepted scientific concept for themselves. More recently, Trumper (1993) carried out a cross-age study
in Israeli elementary and junior high schools in which
he found no significant differences for students' alternative conceptual frameworks about energy in
grades 6 to 9
The preconceptions that children bring to science lessons are known to cause difficulties for the
teacher, and the teaching of conceptual science can
compound this problem if the science conceptions of
teachers themselves are at variance with those accepted by scientists.
In addition to these outcomes, many researchers
(Viennot, 1979; Watts and Gilbert, 1983; Duit, 1984)
have noted students' lack of differentiation between
energy and other physical terms, mainly the concept
of force.
Trumper (1990) carried out a study on Israeli
students, aged 14 to 16. After making some changes
in the definitions of the frameworks, he found 96%
of the students' responses classifiable. The depository
framework became:
2a. The original "depository" framework, which
is of a passive nature ("There is energy in
the battery . . .").
2b. The "active" deposit or "cause" framework.
The energy as "causing things to happen,"
as "being needed for certain processes to occur" ("The electric bulb needs energy in order to light").
In this study (Trumper, 1990), students' alternative conceptual frameworks about energy, both before and after studying the concept in their physics
lessons, were analyzed. The analysis led to two main
results:
1. Before studying physics, the most pervasive
alternative frameworks, held by almost all
students, were: (a) the "anthropocentric"
TEACHERS' CONCEPTIONS ABOUT ENERGY
Knowing more about teachers' preconceptions
in science has become increasingly recognized as essential and some important research has been carried
out in this field (Hollingsworth, 1989; Weinstein,
1989). According to the constructivist perspective,
humans are seen as subjects who actively construct
understanding from experiences using their already
existing conceptual frameworks (Wubbels, 1992). A
constructivist way of teaching assumes the existence
of learners' conceptual schemata and the active application of these when responding to and making
sense of new situations. Kelly's theory of Personal
Constructs (Kelly, 1955) has been adopted by many
science education researchers since his whole approach is based on the metaphor that views the development of "a human being as a scientist." Applied
to science education, this constructivist view supports
teachers who are concerned with the investigation of
students' ideas and who develop ways that incorporate these viewpoints into a learning-teaching dia-
A Longitudinal Study of Physics Students' Conceptions of Energy
logue. Do teachers hold a correct scientific view of
the energy concept themselves?
Kruger, Palacio and Summers (1992) conducted
a comprehensive research into British elementary
teachers' conceptions of energy. They described their
main difficulties in the following way:
1. More than 70% of the teachers showed a
lack of ability to differentiate between force
and energy.
2. Many teachers' did not understand the notion of gravitational potential energy and associated energy mostly with motion.
3. A substantial number of teachers' responses
contradicted the principle of conservation of
energy.
4. Many teachers saw energy as a quasi-material entity.
5. About 70% of the teachers had a vitalistic
view of energy.
Trumper (1996) has recently published a survey
of Israeli physics students' conceptions of energy in
pre-service training for high school teachers. He
found that physics students':
1. Are considerably anthropocentric in their associations, their choice of pictures and their
alternative conceptions.
2. Hold a number of different alternative conceptions when describing physical situations,
instead of the accepted scientific concept.
3. Mostly think that energy is a concrete entity
and not an abstract idea.
4. Mostly do not accept the idea of energy degradation.
5. Mostly confuse the concepts of energy and
force.
How physics students teachers' understanding of
energy develops during their pre-service high school
teacher university program? How do their physics
and Didactics courses influence their energy conceptions? Do university physics students in pre-service
training to be high school teachers finally hold correct scientific views that will eventually allow them
to plan and implement instructional strategies that,
in turn, will lead their future high school students to
achieving a scientific concept of energy? The results
of a longitudinal study dealing with this issue will be
discussed in the next sections.
313
A LONGITUDINAL STUDY
Participants in the present study were drawn from
the greatest university program in Israel which conducts 4-year pre-service training for future high-school
teachers. The study was held during four consecutive
years, comprising 25 students. This population included more than 90% of the students who learned
during the four last years in an Israeli university program that was intended to lead them to a B.Sc. degree
in Physics and a high school teaching certificate.
Students study the basics of the energy concept
and its conservation in 1st year in their mechanics,
electricity and astronomy courses, and in their thermodynamics courses in 2nd year. Besides that, they
learn electromagnetism, waves and optics, physical
chemistry and an introduction to quantum physics in
2nd year. In 3rd year, besides their physics studies
(introduction to statistical mechanics, quantum mechanics, the special relativity theory and a physics
seminar), they watch Physics lessons in a secondary
school and they also practice some teaching. In 4th
year, besides their physics studies (introduction to
nuclear physics, introduction to solid state physics
and a physics seminar) they already work as teachers
in a secondary school. In these last two years, they
study both Physics and Didactic of Physics after
studying some basics of teaching and education during the first two years. Throughout all these years
they learn the necessary mathematics courses and
physics laboratories.
The energy conceptions of the future Physics
teachers were analyzed by means of a two-part written questionnaire that was presented to the same
group on their first day of class for four years running. In the first part of the questionnaire students
were asked to describe eight pictures (Fig. 1) involving the energy concept, in one or two sentences using
the word energy. The pictures in Fig. 1 were taken
from the studies of Bliss and Ogborn (1985) and Gilbert and Pope (1986), with their permission.
Students' descriptions of pictures were classified
according to the frameworks defined by Watts (1983)
together with the "cause" and the broadened "product" framework defined by Trumper (1990). To these,
we added the accepted scientific concept of the Israeli junior high-school curriculum, which we named
the "transformation" framework: "When two systems
interact (i.e., when a process takes place), something
that we name energy, is transferred from one system
314
Trumper
present if there is movement, (b) energy as confused
with force, (c) energy as needed for doing something,
and (d) energy as found in living things only.
Students' responses corresponding to their conceptions in terms of the accepted scientific view were
categorized in the following way:
a. Students were classified as "never/hardly
ever" holding a scientific conception if they
responded correctly between 0% to 24% of
the relevant statements.
b. Students were classified as "sometimes"
holding a scientific conception if they responded correctly between 25% to 75% of
the relevant statements, and
c. Students were classified as "always/nearly always" holding a scientific conception if they
responded correctly from 76% on of the
relevant statements.
Students' responses corresponding to their intuitive views were categorized in the reverse way.
Fig. 1. Pictures illustrating the energy concept.
to another" (Curriculum Development Center,
1978).
Responses to the first part of the questionnaire
were analyzed according to the alternative conceptual frameworks used by students in the description
of the pictures.
The second part of the questionnaire comprised
42 statements together with drawings of different
situations (see appendix to illustrate the nature of
this part). Respondents were asked to respond to
each statement with one of the following responses:
"true," "false," "don't understand" or "not sure."
On the one hand, this part of the questionnaire
was intended to identify students' views in terms of
those currently accepted by scientists. This was conceived by the research in terms of five broad areas:
(a) possession/storage of energy, (b) energy as an abstract idea, (c) conservation of energy, (d) degradation of energy, and (e) recognition of different types
of energy. On the other hand, the second part of the
questionnaire was intended to reach a broader scope
of students' intuitive views of energy, which were divided into four main categories: (a) energy as only
FINDINGS
Responses of Students to the First Part of the
Questionnaire
Table I shows the results obtained in the first
part of the questionnaire.
The Chi-square coefficient among alternative
frameworks during the years was calculated and major differences among years and students' alternative
frameworks were identified. The most salient differences were:
1. The extent to which students held the anthropocentric and cause frameworks decreased.
2. The extent to which students held the deposit and the ingredient frameworks increased.
3. The extent to which students held the product framework was rather stable.
4. The students held a number of different alternative conceptual frameworks when describing physical situations, instead or
besides the accepted scientific concept.
A Longitudinal Study of Physics Students' Conceptions of Energy
Table I. Distribution of Physics Students' Alternative Conceptual
Frameworks, by Years, in Percentagesa
the years, only a minority of the students did
not recognize the possession or storage of
energy by different bodies.
2. There was a significant difference through
the years in students' perception of energy
as an abstract idea. The extent to which students did not perceive energy as an abstract
idea decreased through the years. Anyway,
there was a very low percentage of students
that thought, through all the years, that energy is always or nearly always an abstract
idea.
3. There was a significant difference through
the years in students' acceptance of the conservation of energy law. The reason was a
significant increase, in 3rd and 4th year, in
the extent to which students accepted the
conservation of energy law. This may be due
to the fact that most students watch Physics
lessons during their 3rd year, and teach
Physics during their 4th year in 9th grade
(junior high-school), in which energy is
taught according to energy transformation
and conservation. These issues are being
taught as parallels in the Didactic of Physics
lessons in College.
Year
Cause
Anthropocentric
Product
Deposit
Ingredient
Transformation
a 2
X
1st
2nd
3rd
4th
32
32
12
8
4
12
28
24
12
12
8
16
24
12
12
28
4
20
4
8
16
32
20
20
315
= 83.7, d.f. = 15, P-value = .001.
Responses of Students to the Second Part of the
Questionnaire
Students' Views of Energy in Terms of the Accepted
Scientific Concept
Table II shows the results obtained concerning
students' views of energy in terms of those currently
accepted by scientists. The main findings were:
1. There was a significant increase, through the
years, in students' recognition that different
bodies possess or store energy. During all
Table II. Physics Students' Conceptions on Energy, by Years, in Percentages
Year
1st
2nd
3rd
4th
Possession/
storage of
energya
always/nearly always
sometimes
never/hardly ever
40
56
4
60
36
4
84
8
8
84
12
4
Energy as
an abstract
ideab
always/nearly always
sometimes
never/hardly ever
12
44
44
20
44
36
4
72
24
4
72
24
Conservation
of energyc
always/nearly always
sometimes
never/hardly ever
32
56
12
12
80
8
44
36
20
72
4
24
Degradation
of energyd
always/nearly always
sometimes
never/hardly ever
4
72
24
4
72
24
4
72
24
4
92
4
Recognition
of types of
energye
always/nearly always
sometimes
never/hardly ever
68
20
12
40
56
4
44
44
12
44
44
12
a
X2 = 76.4, d.f. = 6, p-value = .001.
b 2
40.1, d.f. = 6, p-value = .001.
X =
c 2
X = 127.7, d.f. = 6, p-value = .001.
d 2
= 19.7, d.f. = 6, p-value = .003.
X
e
X2 =31.5, d.f. = 6, p-value = .001.
316
Trumper
4. There was a very little difference through
the years in students' acceptance of the idea
that energy may degrade in some cases. A
very low percentage of students, through all
the years, accepted the idea of energy degradation in the relevant cases.
5. There was a significant difference in students' recognition of different types of energy through the years. There was mainly an
increase in the extent to which students were
ambiguous about this issue.
case, through all the years, there was a very
low percentage of students who never, or
hardly ever confused the two concepts.
3. There was a significant difference through
the years in the students' view that energy
is needed to be doing something. There was
a significant increase in the extent to which
students denied it.
4. There was no significant difference through
the years in the students' view that energy
is never, or hardly even found in living things
only. This result is in accordance to the outcome of the first part of the questionnaire,
in which the number of students holding the
"anthropocentric" framework decreased
continuously.
Students' Intuitive Views of Energy
Table III shows the results concerning students'
intuitive views of energy. The main findings were:
1. There was a significant difference through
the years in students' holding the intuitive
view that energy is only present if there is
movement. The number of students denying
it increased through the years. Anyway,
through all the years, most students were
ambiguous about the view that energy is only
present if there is movement.
2. There was a significant difference through
the years for students' confusing the concepts force and energy. There was a significant increase in the extent to which students
were ambiguous about this issue. In any
DISCUSSION
The most important findings of this study can
be summarized as follows. Despite their pre-service
training, future physics high school teachers:
1. Hold a number of different alternative conceptual frameworks when describing physical
situations, instead or besides the accepted
scientific concept.
2. Mostly think that energy is a concrete entity
and not an abstract idea.
Table III. Physics Students' Intuitive Views on Energy, by Years, in Percentages
Year
1st
2nd
3rd
4th
Energy is only
present if there
is movementa
always/nearly always
sometimes
never/hardly ever
4
92
4
4
80
16
8
64
28
4
52
44
Energy is
confused with
forceb
always/nearly always
sometimes
never/hardly ever
56
40
4
56
40
4
40
56
4
32
52
16
Energy is needed
to be doing
somethingc
always/nearly always
sometimes
never/hardly ever
12
4
84
20
4
76
24
4
72
48
4
48
Energy is found
in living things
onlyd
always/nearly always
sometimes
8
4
88
4
4
92
8
4
88
4
4
92
a 2
X
b 2
X
C 2
X
d 2
X
never/hardly ever
= 61.4, d.f. = 6,p-value = .001.
= 40.1, d.f. = 6, p-value = .001.
= 38.0, d.f. = 6, p-value = .001.
= 2.8, d.f. = 6, p-value = .83.
A Longitudinal Study of Physics Students' Conceptions of Energy
3. Mostly do not accept the idea of energy degradation.
4. Mostly confuse the concepts of energy and
force.
5. Hold, at some extent, two intuitive conceptions: a) energy is only present if there is
movement, and b) energy is needed to be
doing something.
There is clearly a need for student teachers'
ideas about energy to be moved away from these perspectives toward the scientific view if they are to lead
children toward a coherent perception of energy and
assess their level of understanding.
The student teachers' difficulties outlined above
are not surprising and can, in part, be explained by
their firm roots in the long experiences that they
have had as students in the education system (high
school and university) and, perhaps, by the influence
of the mass media (Solomon, 1983).
The research outlined above shows that there
are some serious discrepancies between future physics high school teachers' understanding of energy and
the accepted scientific concept. If this fundamental
concept is to be taught well in the secondary school
then every effort must be made to help teachers be
aware of their own conceptions and develop their understanding, both in their Physics and Didactic lessons as it was already done with high school students
(Trumper 1990, 1991).
Many student teachers hold the strong belief
that good teaching is explaining through lecturing
(Wubbels, 1992). He claimed:
Student teachers often think that the real job of a
teacher is to explain things clearly and for years and
years they have experienced this when they were students themselves. Teacher educators, however, want
them often to realize that the primary aim of education is that students learn and understand. This
notion is nearly totally absent in many student teachers' conceptions about teaching (Weinstein, 1989).
Thus, educators must stimulate student teachers to
use group work or class discussion, if appropriate,
to create learning opportunities for students (p.
140).
Adopting this teaching and learning model for
pre-service student teachers education would involve
breaking new ground, extending ideas about the
teaching and learning of children to adult learners.
317
A program of pre-service education adopting this
strategy would be, to that extent, an innovation. Yet
there are good grounds in the state of our current
understanding of children's learning of science, to
suggest that the development and evaluation of such
a program would be a worthwhile undertaking.
REFERENCES
Bliss, J., and Ogborn, J. (1985). Children's choices of uses of energy. European Journal of Science Education 7: 195-203.
Curriculum Development Center (1978). Energy and Its Transformations. Ministry of Education, Israel.
Curriculum of Physics and Chemistry. (1989). Physics and Chemistry, Curriculum for the Junior High School. Ministry of Education, Jerusalem.
Duit, R. (1984). Learning the energy concept in school—Empirical
results from the Philippines and West Germany. Physics Education 19: 59-66.
Gilbert, J., and Pope, M. (1986). Small group discussions about
conception in science: A case study. Research in Science and
Technological Education 4: 61-76.
Gilbert, J., and Watts, D. (1983). Concepts, misconceptions and
alternative conceptions: Changing perspectives in science education. Studies in Science Education 10: 61-98.
Hollingsworth, S. (1989). Prior beliefs and cognitive change in
learning to teach. American Educational Research Journal 26:
160-189.
Kelly, G. (1955). The Psychology of Personal Constructs (Vols. 1
and 2), W W. Norton, New York.
Kruger, C, Palacio, D., and Summers, M. (1992). Survey of English primary teachers' conceptions of force, energy and materials. Science Education 76: 339-351.
Schmid, G. (1982). Energy and its carriers. Physics Education 17:
212-218.
Solomon, J. (1983). Learning about energy: How pupils think in
two domains. European Journal of Science Education 5: 49-59.
Trumper, R. (1990). Being constructive: An alternative approach
to the teaching of the energy concept—part one. International
Journal of Science Education 12: 343-354.
Trumper, R. (1991). Being constructive: An alternative approach
to the teaching of the energy concept—part two. International
Journal of Science Education 13: 1-10.
Trumper, R. (1993). Children's energy concepts: A cross-age study.
International Journal of Science Education 15: 139-148.
Trumper, R. (1996). Survey of Israeli physics students' conceptions
of energy in pre-service training for high school teachers. Research in Science and Technological Education 14: 179-192.
Viennot, L. (1979). Spontaneous learning in elementary dynamics.
European Journal of Science Education 1: 205-221.
Watts, D. (1983). Some alternative views of energy. Physics Education 18: 213-217.
Watts, D., and Gilbert, J. (1983). Enigmas in school science: Students' conceptions for scientifically associated words. Research
in Science and Technological Education 1: 61-81.
Weinstein, C. (1989). Teacher education students' preconceptions
of teaching. Journal of Teacher Education 39: 53-60.
Wubbels, T (1992). Taking account of student teachers' preconceptions. Teaching and Teacher Education 8: 137-149.
318
Trumper
APPENDIX
The picture shows a toy "jumping bug". The person compresses the spring so that the suction cups
stick together and places the bug on the table. After a short time the suction cups come apart,
releasing the spring, and the bug pops up into the air and then falls back onto the table.
1. When the bug's spring is compressed, but before it "pops" up, the toy has energy.
true( ) falsc( ) don't understand( ) not sufe( )
2. When it's moving, after the spring has uncoiled, the bug has energy.
true( ) false( ) don't understand( )
not sure( )
3. The spring's energy is a hidden force within it.
true( ) false( ) don't understand( )
not sure( )
4. The bug has no energy when it's moving upwards.
true( ) false( ) don't understand( )
not sure( )
5. At the top of its flight, when the bug is moving neither up nor down, it has no energy.
true( ) false( ) don't understand( ) not sure( )
6. If you discount air resistance, the bug's energy retrains the same throughout its flight.
true( ) false( ) don't understand( ) not sure( )
7. The bug has no energy when it's moving downwards
true( ) false( ) don't understand( )
not sure( )
8. When it is above the floor and at rest on the table the bug has energy.
true( ) false( ) don't understand( )
not sure( )
The picture shows an electric fire plugged into the wall near to the electricity meter of the house. The
heater is switched on and the bars are glowing.
15. The energy from the power station which supplies this heater did
not exist before it was generated at the station.
true( ) false( ) don't undtrstand( ) not sure( )
16. Only some of the energy from the heater goes into heating up the
room.
true( ) false( ) don't understand() not sure( )
17. Unlike force, which you can feel, energy has no physical
existence since it is merely an abstract idea.
true( ) false( ) don't understand( ) not sure( )
18. The energy from the fire goes into the room and disappears.
true( ) false( ) don't understand( )
not sure( )
19 The rotating disc in the electricity meter indicates the power of the heater
true( ) false( ) don't understand( ) not sure( )
20. An electric fire is less efficient, in scientific terms, for heating the room than a large open log
fire.
true( ) false( ) don't understand( ) not sure( )