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Evaluation of Students’ Understandingof Thermal Concepts in EverydayContextsHye-Eun Chu a , David F. Treagust b , Shelley Yeo c & Marjan Zadnikd
a Natural Sciences and Science Education, National Institute ofEducation, Nanyang Technological University, Singaporeb Science and Mathematics Education Centre, School of Science,Curtin University, Perth, Australiac School of Science, Curtin University, Perth, Australiad Department of Imaging and Applied Physics, School of Science,Curtin University, Perth, AustraliaPublished online: 22 Feb 2012.
To cite this article: Hye-Eun Chu , David F. Treagust , Shelley Yeo & Marjan Zadnik (2012)Evaluation of Students’ Understanding of Thermal Concepts in Everyday Contexts, InternationalJournal of Science Education, 34:10, 1509-1534, DOI: 10.1080/09500693.2012.657714
To link to this article: http://dx.doi.org/10.1080/09500693.2012.657714
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Evaluation of Students’ Understanding
of Thermal Concepts in Everyday
Contexts
Hye-Eun Chua∗, David F. Treagustb, Shelley Yeoc andMarjan Zadnikd
aNatural Sciences and Science Education, National Institute of Education, Nanyang
Technological University, Singapore; bScience and Mathematics Education Centre,
School of Science, Curtin University, Perth, Australia; cSchool of Science, Curtin
University, Perth, Australia; dDepartment of Imaging and Applied Physics, School of
Science, Curtin University, Perth, Australia
The aims of this study were to determine the underlying conceptual structure of the thermal concept
evaluation (TCE) questionnaire, a pencil-and-paper instrument about everyday contexts of heat,
temperature, and heat transfer, to investigate students’ conceptual understanding of thermal
concepts in everyday contexts across several school years and to analyse the variables—school
year, science subjects currently being studied, and science subjects previously studied in thermal
energy—that influence students’ thermal conceptual understanding. The TCE, which was
administered to 515 Korean students from years 10–12, was developed in Australia, using
students’ alternative conceptions derived from the research literature. The conceptual structure
comprised four groups—heat transfer and temperature changes, boiling, heat conductivity and
equilibrium, and freezing and melting—using 19 of the 26 items in the original questionnaire.
Depending on the year group, 25–55% of students experienced difficulties in applying scientific
concepts in everyday contexts. Years of schooling, science subjects currently studied and physics
topics previously studied correlated with development of students’ conceptual understanding,
especially in topics relating to heat transfer, temperature scales, specific heat capacity,
homeostasis, and thermodynamics. Although students did improve their conceptual
understandings in later years of schooling, they still had difficulties in relating the scientific
concepts to their experiences in everyday contexts. The study illustrates the utility of using a
pencil-and-paper questionnaire to identify students’ understanding of thermal concepts in
everyday situations and provides a baseline for Korean students’ achievement in terms of physics
in everyday contexts, one of the objectives of the Korean national curriculum reforms.
International Journal of Science Education
Vol. 34, No. 10, July 2012, pp. 1509–1534
∗Corresponding author: Natural Sciences and Science Education, Nanyang Technological University,
1 Nanyang Walk, Singapore 637616, Singapore. Email: [email protected]
ISSN 0950-0693 (print)/ISSN 1464-5289 (online)/12/101509–26
# 2012 Taylor & Francis
http://dx.doi.org/10.1080/09500693.2012.657714
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Keywords: Thermal physics; Everyday contexts; Conceptual understanding; Alternative
conceptions
Introduction
Over the last three decades, studies have revealed and proposed reasons for the exist-
ence and resilience of children’s and adolescents’ various naıve understandings about
the physical world (Duit, 2009; Osborne & Freyberg, 1985). Despite the diversity of
naıve understandings and theories, different researchers have repeatedly reported
similar results and patterns across age groups. It is also generally agreed that tra-
ditional instruction which does not take into account the existing beliefs of students
is largely ineffective in changing their naıve scientific ideas. Many students leave
school and even university with their intuitive physics understandings unchanged or
existing alongside more accepted scientific views (Meltzer, 2004; Vosniadou, 1994;
White & Gunstone, 1989). Similarly in optics, students were unable to apply scientific
concepts in different contexts even though the contexts were designed to use the same
scientific concept (Chu, Treagust, & Chandrasegaran, 2009).
With regard to students’ understanding of thermal concepts, many researchers have
indicated that students can easily be confused primarily because of the language gap
between the scientific definition and everyday terminology for heat, temperature and
energy (Clough & Driver, 1986; Kesidou, Duit, & Glynn, 1995; Tiberghien, 1985).
Students are very familiar with the terms ‘heat’, ‘temperature’ and ‘energy’ which
they encounter in their everyday lives. Consequently, students think they know the
correct meaning of scientific terminology, but their meaning of the terminology is
very different from that used by experts in science (Carey, 1991; Wiser & Carey,
1983). According to Hewitt (2006), temperature is a measure of the average kinetic
energy of the molecules or atoms. When there are temperature differences between
objects in contact, heat flows from the object at a higher temperature to the object
at a lower temperature. Heat is used mainly to indicate energy flow due to temperature
differences and heat is a process energy form, not a storage energy form in the system
(Kesidou et al., 1995). However, most students think that the objects contain heat.
Once heat has been transferred to an object or substance, it ceases to be heat and
becomes internal energy. Also, many students consider heat as an intensive quantity
and temperature as the amount of heat (Kesidou & Duit, 1993). However, after
they have learned the concept of specific heat capacity in year 11, students tend to
use the specific heat capacity concept to explain thermal equilibrium and to consider
heat as partly an extensive quantity. Many students use the specific heat capacity
concept to describe their understanding related to efficacy to conduct heat or easiness
to get to the thermal equilibrium stage without describing the rate of temperature
change or amount of heat energy transfer (Chiu & Anderson, 2009; Harrison,
Grayson, & Treagust, 1999).
Based on these studies, it is important that students have a clear scientific under-
standing about the terms temperature, heat and energy (namely, internal energy) so
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that they are able to develop their conceptions to explain the everyday phenomena
related to thermal concepts.
This approach is considered important in view of the growing emphasis on the rel-
evance of contextualised science at elementary and secondary school levels (Nentwig
& Waddington, 2005).
In this study, we were interested to learn how well Korean students were able to
respond to questions on thermal concepts that are related to everyday contexts. In
recent times, the Korean national curriculum has incorporated the movement of
science for all and science-technology-society (STS) with an emphasis on the con-
structivist classroom and scientific literacy (Ministry of Education, 1992a, 1992b,
1997). However, in the implemented curriculum, teachers continue to maintain
highly discipline-centred traditional teaching and students have little experience
with these types of physics questions based on everyday life experiences (Kim,
2001; Kwon, 2001; Oh & Kim, 2001). Consequently, this study was designed to
provide a baseline to know how well Korean students are able to answer questions
based on everyday phenomena related to thermal concepts.
Background
Three decades of research related to students’ understanding of thermal con-
cepts have indicated a variety of alternative conceptions held by students aged
12–17 years old. A summary of these findings, primarily from qualitative
studies, using interviews or questionnaires with open-ended responses, is pre-
sented in Table 1. Several factors are known to impede students’ development
of scientifically acceptable conceptions about thermal physics. Students’ accep-
tance that heat is a form of energy is a crucial prior requirement for their devel-
opment of concepts in thermal physics (Kaper & Goedhart, 2002). Also, to be
able to understand the accepted view that heat is energy that moves between
objects at different temperatures, students would first need to differentiate
between heat and ‘cold’, temperature and heat, and fully appreciate the idea
of thermal equilibrium (Arnold & Millar, 1994). Another constraint to under-
standing thermal concepts requires an ontological shift among students that
requires them to regard heat as a process instead of matter (Chi, Slotta, & de
Leeuw, 1994; Wiser & Amin, 2001).
Aims of the Study
This study was conducted to (1) determine the underlying conceptual structure of the
thermal concept evaluation (TCE), (2) investigate students’ conceptual understand-
ing of thermal concepts in everyday contexts across several school years, and (3)
analyse the variables, such as school year, science subjects currently being studied,
and science topics previously studied in thermal energy, that influence students’
thermal conceptual understanding.
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Research Methodology
Instrument
The 26-item TCE questionnaire used in this study was developed and implemented
by Yeo and Zadnik (2001) to assess the extent to which students had attained scien-
tifically acceptable understandings about basic thermal concepts like heat, tempera-
ture, heat conduction and phase changes. Students have a tendency to treat the
Table 1. Previous literature studies on thermal concepts in everyday contexts involving 12–17-
year-olds
Identified alternative conceptions Students’ age Method Author
Heat
There are two types of heat: hot heat
and cold heat
12-year-olds Interviews Erickson
(1979)
Heat is a material substance like a
wave that rises from the road
Temperature
Temperature is an extensive quantity 12-year-olds Interviews Erickson
(1979)
Temperature of boiling water can
exceed 100 8C during boiling
12–15-year-olds Interviews Andersson
(1980)
Temperature is a measure of heat 15–16-year-olds Interviews Kesidou and
Duit (1993)
Boiling
The matter inside bubbles of boiling
water is water, water vapour, heat,
air, smoke, oxygen or carbon dioxide
12-year-olds (also
including 6–11 years
old)
Open-ended
written tests
Bar and Travis
(1991)
Heat conductivity
Metals attract, hold or store heat and
cold
12–14-year-olds
(also including
adults and scientists)
Interviews Lewis and
Linn (1994)
Wool warms things up
Thermal equilibrium
The temperature of different objects
is different even though they have
been placed in the same environment
over an extended period of time
15-year-olds Interviews Clough and
Driver (1986)
17-year-olds Inquiry method
(classroom
discussion)
Harrison et al.
(1999)
12–14-year-olds
(also including
adults and scientists)
Interviews Lewis and
Linn (1994)
General thermal concepts
Students’ confusion because of
dualism of thermodynamics/lack of
understanding in the processes of
cooling (or heating) of pure
substances/understating that does not
rely on the sensations of the body
13–18-year-olds
(also including
teachers)
Open-ended
written tests
Sciarretta et al.
(1990)
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physics that they learn at school purely for the purpose of reproducing the physics on
school tests and examinations without realising the relevance of these concepts in their
everyday lives, often resulting in idiosyncratic understandings of scientific concepts.
For this reason, the items in the TCE were situated in everyday contexts with
which students would be familiar and used limited scientific language in the question-
naire items (Yeo & Zadnik, 2001).
The equivalent Korean questionnaire was back-translated into English. Three
experts in science education and two science teachers worked together to ensure
that the items were correctly translated. Also, two of the Australian authors and
one Korean author met with the Korean–English translator to discuss the back trans-
lation. The back translated items did not show different meanings from the original
items in the English version. The authors made sure that the Korean items were trans-
lated using terms with which students were familiar in everyday contexts and with
minimum use of scientific language.
An example of one of the items in the questionnaire is shown in Figure 1. The items
all involved events that students could experience in a school canteen and were
centred on students’ conversations about these experiences.
Pilot Study
A pilot study was first conducted involving 30–35 students from each school year to
determine the reliability of the items, students’ understanding of the equivalent mean-
ings of terms in translations of the items, and the time required to complete the ques-
tionnaire. Findings from the pilot study indicated that about 50 minutes was sufficient
time and the translated terms in the questionnaire did not cause understanding pro-
blems with students. So, it was confirmed that students had no difficulties in under-
standing the translated terms that were used in the final questionnaire, and the
students were given 50 minutes to complete the 26 items in the actual test.
Participants
A total of 515 Korean high school students from years 10, 11, and 12 participated in
this research. All students had already been introduced to the thermal energy concepts
that were evaluated in the questionnaire during various stages of their science lessons.
Figure 1. An example of an item from the TCE (Yeo & Zadnik, 2001)
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In years 3–10, students were introduced in their study of integrated science to thermal
concepts like temperature change, heat transfer, states of matter, energy, heat conduc-
tivity, boiling/melting point, and thermal dynamic energy. These thermal concepts are
the main emphasised scientific concepts in this research. Some students who were
involved in this research studied physics in years 11 and 12. In year 12, gaseous mol-
ecular motion, thermal dynamic theory and specific heat are introduced, but these
concepts are not among the main scientific concepts explored in this research.
Data Analysis Procedures
Data from the 26-item questionnaire were initially examined for item difficulty (P-
value) and item discrimination index (D-value) based on Lien’s (1971) criteria, i.e.
P-values need to be in the range 30–70 and D-values 20 and over (these two values
are expressed as percentages). Items 9 and 21 failed to meet both the minimum P-
value (30) and the minimum D-value (20) and item 12 exceeded the maximum P-
value (70). Items 9 and 21 were too difficult as less than 30% of the students answered
them correctly and item 12 was too easy as more than 70% of students answered cor-
rectly. Although six additional items did not meet the minimum difficulty value, they
all had acceptable discrimination values and were retained for further analysis.
Subsequently, the remaining 23 items were analysed using SPSS software (version
18.0) beginning with a factor analysis of the items in order to investigate the under-
lying conceptual structure of the TCE. An exploratory factor analysis was performed
and a principal component analysis (PCA) was used to extract the factors followed by
oblique rotation (delta ¼ 0). The Oblique rotation method allows the factors to cor-
relate. The number of factors to be retained was guided by three decision rules:
Kaiser’s criterion (eigenvalues above 1), inspection of screeplot, and Horn’s parallel
analysis (Horn, 1965) conducted using the software developed by Watkins (2000).
The size of eigenvalues obtained from PCA was compared with those obtained
from a randomly generated data set of sample size. Only factors with eigenvalues
exceeding the values obtained from the corresponding random data set were retained
for further investigation.
After each PCA, the items were re-evaluated in the factor solution using specified
criteria. Comrey and Lee (1992) considered items with factor loadings 0.45 as fair
items and factor loadings between 0.32 and 0.45 as poor items, while Hair, Anderson,
Tatham, and Black (1998) and Kline (1994) considered a factor loading of 0.3 as
minimum loading. Moreover, Stevens (2002) considered items with a factor
loading of 0.4 to be fair items and factor loadings of 0.3 to be fair when the sample
size is greater than 300. In our research, the cut-off loading was made at 0.3
because our sample size was 515 with 13 of the 19 items showing factor loadings
greater than 0.45.
The percentage of students’ correct responses to each of the items contributing to
the underlying conceptual structure was then calculated. The correlations between
the mean scores of the conceptual groups were computed and the multivariate analy-
sis of variance (MANOVA) procedure was used to investigate the main factors that
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influenced students’ conceptual understanding of thermal concepts. The standar-
dised mean scores (50 + Z score × 10) of the four conceptual groups of items
were the dependent variables, while school year, subjects currently studied, and
physics topics previously studied relating to heat transfer, specific heat capacity,
and thermodynamics were the independent variables. To find out the impact of the
independent variables on the dependent variable (the standardised mean scores of
the four conceptual groups of items), the eta squared effect size statistics were com-
puted. The eta squared values inform us how strongly the independent variables influ-
enced the dependent variable.
Result and Discussion
Item Analysis of the TCE
Investigating the underlying conceptual structure. Inspection of the pattern matrix
showed the clear factor loadings of each item while the analysis of the structure
matrix indicated good discrimination among the four components (see Table 2).
The conceptual groups were: (1) heat transfer and temperature changes, (2)
boiling, (3) heat conductivity and equilibrium, and (4) freezing and melting. Each
conceptual group involves a particular set of related items. A description of the
items in each of the four conceptual groups and the deleted items are presented in
Table 3.
Items 3 and 20 had relatively low loadings and hence were deleted. In Items 1 and 2,
students have to consider the surroundings. For example, in item 1, the temperature
of ice in a refrigerator’s freezer compartment is decided by the temperature of the
freezer compartment. In item 3 on the other hand, the higher temperature of the sur-
rounding air may have distracted them from the temperature of the ice pieces on the
bench, leading them to believe that the temperature of the ice on the bench-top was
greater than 0 8C. item 20 was the only question in this questionnaire that concerned
air convection. Items 8 and 19 were about boiling water/soup under different press-
ures and they could not be loaded into boiling concept group 2 because items in
the boiling concept group were about the temperature of the boiling point of water
at the ground level. Item 8 showed relatively low loading, so it was deleted. Item 19
was loaded in group 1 (with factor loading 0.31, correlation 0.38 between item 19
and factor 1) and group 3 (with factor loading 0.37, correlation 0.44 between item
19 and factor 3). Item 19 was deleted because it was loaded in two inappropriate con-
ceptual groups and the factor loading values in the two conceptual groups were very
close to each other. However, item 16 was retained in conceptual group 3, heat con-
ductivity and equilibrium, even though the item was loaded in group 1 (with factor
loading 0.3, correlation 0.1 between item 16 and group1) and group 3 (with factor
loading 0.5, correlation 0.5 between item 16 and group 3). Item 16 is about conduc-
tivity in different materials, wood and metal and involved attaining temperature equi-
librium as a result of heat conduction. Item 16 was loaded in two conceptual groups
and showed relatively higher loading in conceptual group 3.
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Table 2. Factor loadings of the 19 items in the TCE with P- and D-values
Item P D
Components
1 2 3 4
Pattern
matrix
Structure
matrix
Pattern
matrix
Structure
matrix
Pattern
matrix
Structure
matrix
Pattern
matrix
Structure
matrix
Q25 46 68 0.61 0.60 20.12 20.07 20.05 0.05 0.09 0.14
Q15 58 71 0.54 0.55 20.10 20.06 0.10 0.18 20.03 0.04
Q22 52 71 0.52 0.54 20.01 0.03 20.03 0.07 0.16 0.21
Q13 36 71 0.47 0.51 0.02 0.05 0.22 0.30 0.16 0.24
Q23 23 59 0.46 0.47 0.16 0.19 0.06 0.12 20.05 0.00
Q7 62 42 0.41 0.38 0.08 0.12 20.11 0.08 20.23 0.20
Q10 42 88 0.31 0.39 0.25 0.27 0.24 20.31 0.20 20.26
Q5 36 56 20.10 20.02 0.77 0.76 0.10 0.10 0.13 0.13
Q4 22 32 0.12 20.01 0.72 0.73 20.12 20.11 20.02 20.02
Q6 28 34 20.01 0.16 0.31 0.31 20.05 20.07 20.12 20.13
Q24 18 34 20.06 20.00 20.05 0.06 0.64 0.63 20.12 0.05
Q14 23 69 20.01 0.02 0.13 20.13 0.63 0.62 0.05 20.13
Q16 33 64 0.33 0.10 20.05 20.03 0.47 0.50 20.11 20.02
Q26 31 51 0.00 0.38 20.16 20.17 0.38 0.39 0.07 0.12
Q17 24 47 0.17 0.05 20.06 20.04 0.37 0.39 20.02 0.04
Q18 17 36 20.07 0.22 0.27 0.26 0.35 0.35 0.09 0.11
Q2 58 56 20.19 0.01 0.00 20.02 0.13 0.18 0.68 0.69
Q1 50 61 0.12 0.17 20.12 20.12 20.04 0.06 0.68 0.69
Q11 46 54 0.20 20.10 0.11 0.12 20.27 20.18 0.49 0.47
Initial eigenvalues 2.5 1.4 1.3 1.3
Percentage of
variance
13.9 8.0 7.3 6.7
Conceptual groups: component 1, heat transfer and temperature changes; component 2, boiling; component 3, heat conductivity and equilibrium;
component 4, freezing and melting. Figures in bold indicate major loadings for each item.
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Table 3. Description of TCE items in the four conceptual groups, including P- and D-values
Conceptualgroup
Itemno. Item description P D
1 Heat transfer andtemperature changes
7 Predicting temperature of mixture of water 62 4215 Comparing magnitude of ‘coldness’ resulting
from temperature decrease announced in aweather forecast
58 71
22 Inflating a bicycle tyre resulting in warming upof pump
52 71
23 Wearing sweaters in cold weather 52 5925 Producing superconductor magnets at low
temperatures46 68
10 Comparing the temperature of a cold can ofcoke with that of the bench top beneath the can
42 88
13 Transferring heat energy from hot boiled eggs tocold water
36 71
2 Boiling 5 Predicting temperature of continuously boilingwater
36 56
6 Predicting temperature of steam in contact withboiling water
28 34
4 Predicting initial temperature of boiling water 22 323 Heat conductivity
and equilibrium16 Explaining why metal ruler feels colder than
wooden ruler33 64
26 Measuring of temperature of dolls wrapped inblankets
31 51
17 Predicting room temperature based on coolingeffect of bottles wrapped with wet and drywashcloths
24 47
14 Comparing ‘warmness’ and coldness’ of plasticand metal
23 69
24 Comparing temperatures of wooden and iceparts of ice-lolly
18 34
18 Explaining why the milk carton from therefrigerator feels colder than the one from thebench top
17 36
4 Freezing and melting 2 Predicting temperature of ice water when icecubes have stopped melting
58 56
1 Predicting temperature of ice-blocks stored in afreezer
50 61
11 Comparing heat loss by equal masses of ice andice water at 0 8C in a freezer
46 54
Deleted items 12 Predicting what is in bubbles that form in
the boiling water
72 56
3 Predicting temperature of ice almost melted andlying in a puddle of water
59 61
8 Preparing tea at high altitude 50 8319 Cooking of soup in a pressure cooker 40 73
9 Predicting temperature of plastic bottle
and coke in the plastic bottle that has been
in a refrigerator overnight
26 20
20 Predicting suitable shelf in the electric oven tocook cakes well
24 24
21 Predicting why sweat cools you down 14 5
Italicised and bold items did not meet Lien’s criteria.
P, P-value; D, D-value.
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Even though the factor analysis showed four distinct conceptual groups, the
reliability of three groups was low (0.4–0.5). However, the Cronbach alpha reliability
for the 19 items was 0.59. According to Nunally and Bernstein (1994), a Cronbach
alpha reliability coefficient greater than 0.7 indicates a high reliability while values
in the range 0.5–0.7 indicate moderate reliability and are acceptable in studies of a
cognitive nature. The Cronbach’s alpha reliabilities for both the boiling, freezing
and melting conceptual groups were low because the items in the two conceptual
groups involved the thermodynamic dualism of concepts like, state and process,
and heat and temperature (Sciarretta, Stilli, & Vicentini Missoni, 1990). Several of
the items in the heat conductivity conceptual group also required background under-
standing of heat transfer to reach an equilibrium state. These kinds of conceptual con-
tinuity in the conceptual groups decreased the internal consistency reliability of the
items in the categories.
Nunally and Bernstein (1994) suggest that for good item construction, the item
content should be homogenous, and factor analysis as well as item difficulty and
item discrimination indices should be considered together when selecting items relat-
ing to particular concepts. The items in this research can be used to identify important
students’ alternative conceptions because although students were introduced to these
concepts in their earlier studies, most students were unable to make connections with
the contexts of the items involved. Consequently, these 19 items in the four concep-
tual groups were used to explain students’ conceptions in thermal concepts across the
school years 10–12.
Students’ Correct Responses
Items related to everyday contexts in the heat conductivity and the equilibrium con-
ceptual group and the boiling conceptual group elicited lower correct answers than
the other two conceptual groups. The percentages of the group means of correct
responses for these two conceptual groups were 29% and 24%, respectively. The per-
centages of students’ correct responses to each of the 19 items in four conceptual
groups across the school years are summarised in Table 4.
In general, there was no clear cut progression of conceptual development across the
school years. For example, the percentage of correct responses to items 7 and 11 for
year 10 was higher than that for years 11 and 12. Also, year 10 students showed higher
percentages of correct responses than year 11 students in items 23, 5, and 4. For items
15, 25, 10, and 6, the percentages of correct responses in year 11 were higher (or
same) than in year 12.
The statistical analysis of the influence of school year on students’ conceptual
understating is provided in Table 7 in a subsequent section.
Students’ Alternative Conceptions
Students’ alternative conceptions across school years 10–12 are summarised in Table
5. For multiple-choice items with four responses, scientifically inappropriate
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Table 4. The percentage of students’ correct responses to the items in the four conceptual groups
across the school years
Item no. Correct responses
Percentage of correct responses
Y10 Y11 Y12 Over-all
Group
mean
Heat transfer and temperature changes
7 When two cups of water at 40 8C each are
added to one cup of water at 10 8C, the
resulting temperature is not the average of the
two temperatures
68 57 60 62
15 A temperature of 5 8C is not twice as cold as a
temperature of 10 8C42 69 63 58 50
22 A bicycle pump becomes hot when it is used to
pump up a tyre because energy has been
transferred from the compressed air to the
pump.
47 51 57 52
23 We wear sweaters in cold weather to reduce
heat loss from our bodies
52 47 56 52
25 Super-conducting magnets can be produced at
a temperature of 2260 8C, close to the lowest
temperature possible (i.e. 2273 8C)
42 52 44 46
10 When a cold can of coke is picked up from a
bench top, the space that was underneath the
can would be colder than the rest of the bench
top because some heat energy has been
transferred from the bench to the can
35 46 46 42
13 When boiled eggs are cooled by placing them
in cold water energy is transferred from the
eggs to the water
27 38 44 36
Boiling
5 As the water in the kettle continues to boil for
some time, the most likely temperature of the
boiling water is still 98 8C
37 28 43 36 29
6 The temperature of the steam above the
boiling water in the kettle is most likely to be
98 8C
27 32 26 28
4 The most likely temperature of water boiling in
a kettle is 98 8C (not 88 8C or 110 8C).
22 19 25 22
Heat conductivity and equilibrium
16 Metal is colder than wood when we touch it,
because metal conducts energy more rapidly
than wood
28 33 40 33
26 The constant temperature of dolls wrapped in
blankets was not due to the materials in the
blankets or the dolls
30 31 33 31 24
(Continued)
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responses selected by more than 25% of respondents were considered as alternative
conceptions in this research, while items with five response values greater than 20%
(as in Items 11 and 26) were considered as alternative conceptions.
Heat transfer and temperature changes. The items related to everyday life in the heat
transfer and temperature changes conceptual group mainly required students to
have a clear understanding about the difference between heat and temperature.
However, students’ demonstrated confusion about these two concepts. In Table 5,
students from year 10 showed heat is proportional to temperature (item 15, 31%)
and students from all school years suggested that temperature could be transferred
Table 4. (Continued)
Item no. Correct responses
Percentage of correct responses
Y10 Y11 Y12 Over-all
Group
mean
17 When two glass bottles containing water at
20 8C were wrapped separately with a wet and
a dry washcloth, the temperature of the water
some time later in each bottle was 18 8C and
22 8C, respectively. The most likely room
temperature during this experiment was 26 8C(not 20 8C or 21 8C or 18 8C)
14 26 33 24
14 Although metal chairs may feel colder than
wooden ones, both chairs are at the same
temperature
18 22 29 23
24 The wooden stick and the ice part of an ice-
lolly taken out of a freezer are at the same
temperature because both parts are in contact
with each other
14 15 24 18
18 The colder carton of choc milk conducts heat
faster than the warmer carton of choc milk
11 20 21 17
Freezing and melting
2 The temperature of water produced by melting
ice is most likely to be 0 8C (and not 210 8C or
5 8C or 10 8C)
54 58 63 58 51
1 The temperature of ice blocks that are stored
in the freezer compartment of a refrigerator
would most likely to be 210 8C (and not 0 8Cor 5 8C)
42 48 59 50
11 When 100 g of ice at 0 8C and 100 g of water at
0 8C are both placed in a freezer, the latter
would eventually lose the greater amount of
heat energy
48 44 46 46
Y10, year 10 (n ¼ 178); Y11, year 11 (n ¼ 166); Y12, year 12 (n ¼ 171); total sample (N ¼ 515).
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from the body to another (Items 13 and 22, 14–36%). The most common alternative
conception in this group for all school years was that ‘hot and cold are different, not on
opposite ends of a continuum’ (Items 10 and 13, 21–40%).
Table 5. Frequencies of students’ alternative conceptions across the school years
Students’ alternative conceptions
Item no
(choices)
School year
Year 10
(N ¼ 178)
Year 11
(N ¼ 166)
Year 12
(N ¼ 171)
Heat transfer and temperature changes
Two different temperatures can be added up and
averaged
Q7 (b) 40 (23) 56 (34) 47 (28)
Temperature can be transferred from one body
to another
Q13 (a) 64 (36) 32 (19) 40 (23)
Q22 (b) 30 (17) 23 (14) 34 (20)
Materials like wool have the ability to warm
things up
Q23 (d) 43 (23) 52 (31) 48 (28)
‘Hot’ and ‘cold’ are different, not at opposite
ends of a continuum
Q10 (a) 72 (40) 38 (23) 46 (27)
Q13 (b) 47 (26) 45 (27) 36 (21)
There is no limit to the lowest temperature that
can be reached
Q25 (b) 46 (26) 42 (25) 55 (32)
Heat is proportional to temperature Q15 (a) 55 (31) 17 (10) 19 (11)
Boiling
Heating always results in an increase in
temperature
Q4 (c) 42 (23) 54 (33) 43 (25)
The boiling point of water is 100 8C Q4 (d) 80 (45) 76 (46) 76 (44)
The temperature at the boiling does not remain
constant
Q5 (c) 68 (38) 82 (50) 69 (40)
Steam above boiling water in a kettle is at a
temperature greater than 100 8CQ6 (c) 59 (33) 67 (40) 82 (48)
Heat conductivity and equilibrium
The amount of heat in an object depends on the
material that the object is made up of
Q14 (d) 98 (55) 94 (57) 70 (41)
Q24 (c) 63 (35) 58 (35) 51 (30)
Metal ruler feels cooler than wooden one
because metal is good radiator
Q16 (d) 39 (22) 29 (18) 38 (22)
Materials like wool have the ability to warm
things up
Q17 (b) 46 (26) 39 (24) 38 (22)
Objects at different temperatures that are in
contact with each other do not necessarily move
towards the same temperature
Q17 (c) 81 (46) 60 (36) 59 (35)
‘Hot’ and ‘cold’ are different, not at opposite
ends of a continuum.
Q18 (a) 67 (38) 48 (29) 55 (32)
Some materials are difficult to heat: they are
more resistant to heating
Q26 (c) 61 (34) 60 (36) 58 (34)
Freezing and melting
Ice is always at 0 8C Q1 (b) 88 (50) 70 (42) 57 (33)
Heat is proportional to temperature Q11 (c) 33 (19) 36 (22) 29 (17)
Water cannot be at 0 8C Q2 (c) 59 (33) 55 (33) 42 (25)
The numbers in bold indicate alternative conceptions. Percentages are denoted in parentheses.
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These two alternative conceptions were found to be context—independent as illus-
trated in Table 6 where students displayed the same alternative conceptions in two
different items. For example, among the 64 students in year 10 who chose the alterna-
tive conception ‘Temperature can be transferred from one body to another’ in item 13,
11 students (17%) chose the same alternative conception again in item 22 (see Table 6).
Boiling. The alternative conceptions in this group were most prevalent among all
year levels. The context of the three items was about boiling water in a kettle. Students
in all the year groups were already familiar with the concepts associated with phase
changes. However, 30–50% of students indicated that ‘the temperature at the
boiling point does not remain constant’ and that ‘steam in the kettle is at a tempera-
ture higher than 100 8C’. Also, 44–46% of students from all years displayed the naive
conception that ‘the temperature of boiling water is always 100 8C’. These very basic
conceptual understandings in thermal physics are not given sufficient emphasis in the
Korean school curriculum and also there is limited inclusion of everyday life examples
that apply these basic scientific conceptions about heat and temperature.
Heat conductivity and equilibrium. The items in this conceptual group involve
context-related experiences in different everyday phenomena. Students are required
to apply the scientific concept of heat conductivity between two materials at different
temperatures until a state of equilibrium is reached. At the same time, students should
be aware that the different materials have different heat conductivities, even though
they are in a state of equilibrium at the same temperature. As many as 35–55% of stu-
dents from all school years indicated that ‘containing heat is a property of materials’ as
shown in item 14 (involving comparing the ‘coldness’ of chairs made from two differ-
ent materials, plastic and metal) and item 24 (involving comparing the ‘coldness’ of
the wooden stick and ice part of an ice-lolly). These items were context dependent.
For example, among the 98 students in year 10 who chose the alternative conception
‘The amount of heat in an object depends on the material that the object is made up
Table 6. Percentages of students who held the same alternative conceptions in different contexts
Students’ alternative conceptions Item no (choices)
School year
Y10 Y11 Y12
Temperature can be transferred from
one body to another
Q13 (a) and Q22 (b) 11 (17) 7 (22) 11 (28)
‘Hot’ and ‘cold’ are different, not at
opposite ends of a continuum
Q13 (b) and Q10 (a) 20 (28) 17 (45) 13 (28)
The amount of heat in an object
depends on the material that the
object is made up of
Q14 (d) and Q24 (c) 34 (35) 35 (37) 28 (40)
Percentages are denoted in parentheses.
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of’ in item 14, 34 students (34%) chose the same alternative conception again in item
24 (see Table 6).
In item 17 (involving heat conduction from bottles of cold water wrapped separately
with a wet and a dry washcloth) 35–46% of students from all school years suggested
that ‘equilibrium is not a necessary process for objects at different temperatures that
are in contact with each other’, that is objects at different temperature that are in
contact with each other, do not necessarily reach an equilibrium temperature. Also,
in item 18 (comparing heat conduction to a hand from a cold milk carton and from
a warm milk carton) 29–38% of students from all school years displayed that the
carton feels colder because the cold milk carton contains more coldness than the
warm milk cartoon.
Freezing and melting. Items in this conceptual group include ice blocks in the freezer
(item 1), ice blocks in water (item 2) and ice and water both at 0 8C in the freezer (item
11). This conceptual group is related to basic scientific concepts in thermal physics,
yet 33–50% of students’ from all school years indicated that ‘ice is always at 0 8C’
and 25–33% of students’ from all school years suggested that ‘water cannot be at
0 8C’. Also 22% of students from year 11 held the alternative conception in response
to item 11 that ‘heat is proportional to temperature’ so, they suggested that ‘ice at 0 8Cand water at 0 8C in the freezer both lose the same amount of heat’.
All four conceptual groups are essential for the development of students’ under-
standing of thermal physics concepts. The heat transfer and temperature changes con-
ceptual group that lays the foundation for the understanding of all other concepts;
students need to have a clear understanding of the difference between heat and temp-
erature in order to understand the other concepts. Based on correlation analysis,
involving the four conceptual groups, the heat transfer and temperature changes
group correlated significantly with (1) boiling conceptual group (r ¼ 0.1, P ≤0.05), (2) the heat conductivity and equilibrium conceptual group (r ¼ 0.3, P ≤0.005), (3) freezing and melting conceptual group (r ¼ 0.2, P ≤ 0.005). Based on
Cohen’s (1988) suggestion, the significant Pearson coefficient in this research can
be considered as a small correlation or medium correlation (range 0.10–0.29: small
correlation, range 0.30–0.49: medium correlation).
No significant correlation was found between other conceptual groups in this
research. As indicated in the Introduction, the other main reason for the existence
of students’ alternative conceptions may be due to differences in the meanings of
scientific terms when they are used in everyday language. The terms, ‘coldness’ and
‘hotness’, for example, are often used to imply heat transfer between objects.
Analysis of the Influence of the Independent Variables
The impact of several independent variables—school year, science subjects currently
studied and previously studied topics in thermal energy—on students’ understanding
of thermal energy concepts were evaluated in this research.
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School Year
Students’ mean scores in the four conceptual groups according to their school years
are shown in Table 7. For the heat transfer and temperature changes conceptual
group and heat conductivity and equilibrium conceptual group there were no mean
difference between students in years 10 and 11 and years 11 and 12, but there were
significant mean differences in years 10 and 12. However, the eta squared values indi-
cate that only 2–4% in the variance of mean scores in these two conceptual groups can
be explained by the different year groups, suggesting that the influence of school year
on the conceptual understating of heat transfer and temperature changes and heat
conductivity and equilibrium is very limited. (Interpretation of eta squared values:
0.01 ¼ small effect; 0.06 ¼ moderate effect; 0.14 ¼ large effect). Similarly, for the
conceptual groups boiling, and melting and freezing, there were no significant differ-
ences in the mean scores across school years 10–12.
Science Subjects Currently Studied
Students in years 10–12 studied different subjects. All students studied general
science when they were in year 10. If students intend to study engineering or
science majors, they usually choose more science subjects in years 11 and 12. In
this study, year 10 students studied only general science, while students in years 11
and 12 studied one or more subjects chosen from life science, physics and chemistry.
The breakdown of subjects studied was: (1) general science—year 10 (N ¼ 178), (2)
life science—year 11 (N ¼ 76) and year 12 (N ¼ 81), and (3) physics and chemistry—
year 11 (N ¼ 90) and year 12 (N ¼ 90).
The results of MANOVA to investigate the impact of science subjects currently
studied on the four conceptual groups of thermal concepts are shown in Table 8.
Table 7. Students’ standardised mean scores in the four conceptual groups based on school years,
from MANOVA results
School year
Conceptual groups
Heat transfer and
temperature changes
Mean + SD
Boiling
Mean + SD
Heat conductivity
and equilibrium
Mean + SD
Melting and
freezing
Mean + SD
Year 10 (N ¼ 178) 48.1 + 9.2a 49.9 + 10.6 47.6 + 8.9a 49.0 + 10.0
Year 11 (N ¼ 166) 50.8 + 10.3ab 49.2 + 9.6 50.1 + 9.3ab 49.6 + 10.1
Year 12 (N ¼ 171) 51.2 + 10.3b 50.9 + 9.7 52.5 + 11.1b 51.4 + 9.8
F 4.9∗ 1.3 11.0∗∗ 2.8
Eta squared 0.02 0.01 0.04 0.01
Different superscripts indicate that there are significant differences between year levels.
∗P ≤ 0.05.
∗∗P ≤ 0.005.
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Students who were studying chemistry and physics showed significantly better under-
standing than students who were studying general science or life science in the heat
transfer and temperature changes and heat conductivity and equilibrium conceptual
groups. Also, they had significantly better understanding comparing to other students
about the melting and freezing conceptual group, while students who were studying
general science showed significantly better understanding than students who were
studying life science in this conceptual area. Science subjects currently studied did
not have any influence on the understanding of boiling concepts. The impact of
science subjects currently studied on the heat transfer and temperature changes and
the melting and freezing conceptual groups displayed medium eta squared effect
size values of 0.10 and 0.11, respectively.
Previously Studied Science Topics Related to Thermal Concepts
Students were requested to select the science topics that they had previously studied
from a list of eight topics, namely heat, heat and cooling, heat transfer, temperature
scales, phase changes, specific heat capacity, homeostasis, and thermodynamics.
The corresponding MANOVA results for each of the topics concerned are summar-
ised in Table 9.
Heat topic. There was no significant difference across all four conceptual groups in
the mean scores of the responses to the TCE between students who had previously
studied the topic on heat and those who had not.
Table 8. Students’ mean scores in the four conceptual groups based on science subjects currently
studied, from MANOVA results
Current studying
subjects
Conceptual groups
Heat transfer and
temperature changes Boiling
Heat conductivity
and equilibrium
Melting and
freezing
Mean + SD Mean + SD Mean + SD Mean + SD
General Science
(N ¼ 178)
48.1 + 9.2a 49.9 + 11.0 47.6 + 8.9a 49.0 + 10.0b
Life Science
(N ¼ 157)
47.1 + 8.9a 50.2 + 8.9 49.0 + 7.9a 46.2 + 8.7a
Chemistry and
Physics (N ¼ 180)
54.3 + 10.2b 50.0 + 10.3 53.3 + 11.7b 54.3 + 9.5c
F 29.5∗∗ 0.03 16.6∗∗ 32.2∗∗
Eta squared 0.10 0.00 0.06 0.11
Different superscripts indicate that there are significant differences between year levels.
∗∗P ≤ 0.001
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Table 9. Students’ means scores in the four concept categories based on previously studied science topics related to thermal concepts, from MANOVAresults
Topic
Conceptual groups
Heat transferand temperature
changes Boiling
Heatconductivity
and equilibriumMelting and
freezing
Heat (Y ¼ 390,N ¼ 104)
Mean + SD Y 50.6 + 10.0 50.0 + 9.9 50.2 + 10.2 50.6 + 10.2N 49.0 + 9.9 50.0 + 10.1 49.7 + 9.8 48.9 + 10.0
F 2.3 0.00 0.2 2.4Eta squared 0.01 0.00 0.00 0.01
Heating andcooling (Y ¼ 313,N ¼ 181)
Mean + SD Y 52.0 + 10.0 50.1 + 10.1 51.0 + 10.3 50.5 + 9.7N 47.3 + 9.3 50.0 + 9.9 48.4 + 9.5 50.0 + 11.0
F 26.7∗∗ 0.01 7.3∗ 0.4Eta squared 0.05 0.00 0.02 0.00
Heat transfer(Y ¼ 283, N ¼ 211)
Mean + SD Y 52.8 + 9.9 50.8 + 10.2 51.5 + 11.1 51.2 + 10.1N 46.9 + 9.1 48.9 + 9.7 48.1 + 8.1 49.0 + 9.8
F 45.4∗∗ 4.6∗ 13.8∗∗ 5.5∗
Eta squared 0.09 0.01 0.03 0.01
Temperaturescales (Y ¼ 267,N ¼ 227)
Mean + SD Y 52.4 + 10.2 50.8 + 10.7 51.6 + 10.7 51.2 + 9.9N 47.8 + 9.2 49.1 + 9.4 48.3 + 9.0 49.2 + 10.1
F 29.9∗∗ 3.5 13.4∗∗ 5.0∗
Eta squared 0.06 0.01 0.03 0.01Phase changes(Y ¼ 102, N ¼ 392)
Mean + SD Y 55.2 + 10.1 50.4 + 10.5 55.2 + 12.0 53.8 + 9.4N 49.0 + 9.6 50.0 + 9.9 48.7 + 9.0 49.3 + 10.0
F 34.0∗∗ 0.2 36.5∗∗ 17.1∗∗
Eta squared 0.07 0.00 0.07 0.03
Specific heatcapacity (Y ¼ 244,N ¼ 250)
Mean + SD Y 53.5 + 10.1 50.3 + 10.3 51.9 + 11.2 52.3 + 9.9N 47.1 + 8.8 49.8 + 9.8 48.3 + 8.5 48.3 + 9.8
F 56.9∗∗ 0.3 15.9∗∗ 20.84∗∗
Eta squared 0.10 0.00 0.03 0.04
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Homeostasis(Y ¼ 257, N ¼ 237)
Mean + SD Y 53.3 + 10.2 50.4 + 10.4 52.2 + 11.1 51.8 + 9.6N 47.0 + 8.6 49.6 + 9.6 47.8 + 8.3 48.6 + 10.2
F 55.5∗∗ 0.9 24.3∗∗ 12.9∗∗
Eta squared 0.10 0.00 0.05 0.03
Thermo-dynamics (Y ¼ 100,N ¼ 394)
Mean + SD Y 54.0 + 10.5 52.4 + 11.5 53.9 + 11.6 52.4 + 9.9N 49.3 + 9.6 49.4 + 9.5 49.1 + 9.4 49.7 + 10.0
F 17.6∗∗ 7.2∗ 18.8∗∗ 5.9∗
Eta squared 0.03 0.01 0.04 0.01
Y indicates ‘yes’; N indicates ‘no’.
∗P ≤ 0.05.
∗∗P ≤ 0.005.
Stu
den
ts’U
ndersta
ndin
gin
Every
day
Con
texts
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Heating and cooling. Students who had previously studied this topic achieved signifi-
cantly higher mean scores in the heat transfer and temperature changes and heat con-
ductivity and equilibrium conceptual groups than those who had not. There was no
discernable difference in students’ achievement in the other two groups. The
medium-sized eta squared value for the heat transfer and temperature changes
group indicates a variance of 5% in the mean scores between students who had and
those who had not previously studied the topic. There was, however, only limited
influence on the heat conductivity and equilibrium conceptual group as indicated
by the small eta squared value of 0.02.
Heat transfer. There were significant differences in the mean scores of students who
had previously studied this topic and those who had not for all the four conceptual
groups, with the greatest influence being on the heat transfer and temperature
changes conceptual group (indicated by a medium-sized eta squared value of 0.09).
The influence on the mean scores was relatively small in all the other three groups.
Temperature scales. Students who had previously studied this topic achieved signifi-
cantly higher mean scores than those who had not done so in three conceptual
groups, other than the boiling group. Also, the greatest influence was on the heat
transfer and temperature changes group, indicated by the medium-sized eta
squared value of 0.06. A variance of only 1–3% in the mean scores of the other
three conceptual groups could be explained by the influence of this topic.
Phase changes. The trend was similar as in the previous topic, but this time medium-
sized eta squared values for heat transfer and temperature changes and the heat con-
ductivity and equilibrium conceptual groups indicate a variance of 7%, respectively, in
the mean scores between students who had and those who had not previously studied
phase changes.
Specific heat capacity. The differences in the mean scores were again significant for all
groups except the boiling conceptual group. The greatest influence was on the heat
transfer and temperature changes conceptual group, indicated by a medium eta
squared value accounting for 10% of the difference in the variance of the mean
scores of the two groups of students. Less than 4% in the variance of the difference
in the mean scores of the other three groups could be explained by the influence of
this topic.
Homeostasis. The trend was similar as in the three previous topics with the most sig-
nificant difference in the mean scores being for the heat transfer and temperature
changes conceptual group. The influence of the homeostasis topic on this group is
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evident from the medium-sized eta squared value accounting for 10% of the differ-
ence in the variance of the mean scores of the two groups of students.
Thermodynamics. There were statistically significant differences in the mean scores
of the responses to the TCE across all four conceptual groups between students
who had previously studied the topic on thermodynamics and those who had not.
The eta squared values for the these four conceptual groups indicate that only 1–
4% in the variance of the mean scores of students who had previously studied this
topic and those who had not could be explained by the influence of the thermodyn-
amics topic.
Conclusions
The aims of this research were to (1) determine the underlying conceptual structure of
the TCE, (2) investigate students’ conceptual understanding of thermal concepts in
everyday contexts across several school years, and (3) analyse the variables, such as
school year, science subjects currently being studied, and science subjects previously
studied in thermal energy, that influence students’ thermal conceptual understanding.
The Underlying Conceptual Structure of the TCE
A factor analysis of students’ responses to the 26-item TCE questionnaire of Yeo and
Zadnik (2001) resulted in a psychometric structure with 19 items comprising four
conceptual groups, namely, (1) heat transfer and temperature changes, (2) boiling,
(3) heat conductivity and equilibrium, and (4) freezing and melting. Seven items
were omitted because they did not distinctly evaluate the concepts in any of the
four conceptual groups. Items in two conceptual groups, heat transfer and tempera-
ture changes, and melting and freezing were found to have appropriate P-values
(item difficulties) and D-values (item discrimination index). However, items in the
other two conceptual groups (heat conductivity and equilibrium, and boiling) were
found to have low P-values but appropriate/high D-values. The items in these two
latter groups assessed understanding of fundamental thermal concepts that students
had previously learned in years 7–10, yet the students in this sample displayed limited
understanding. Subsequently, these four-item conceptual groups were used to evalu-
ate students’ understanding of thermal physics concepts in everyday contexts.
Students’ Conceptual Understanding of Thermal Concepts in Everyday Contexts
Three findings have emerged from this study:
(1) A lower percentage of students provided correct answers to the items in the heat
conductivity and equilibrium group (group mean: 24%) and the boiling group
(group mean: 29%) compared to the other two conceptual groups, heat transfer
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and temperature changes (group mean: 50%) and melting and freezing (group
mean: 51%) groups.
(2) The students’ mean scores of the heat transfer and temperature changes concep-
tual group correlated significantly with the scores from all the other three concep-
tual groups, with the highest correlation being with the heat conductivity and the
equilibrium conceptual group.
(3) Several alternative conceptions from all four conceptual groups were held by stu-
dents in all years. A common alternative conception among students from all
school years involved the concepts of boiling, freezing and melting points. Stu-
dents generally did not associate these temperatures with phase changes that
could affect their values. Other typical alternative conceptions among students
from all school years included the inability to distinguish between heat (‘hot’
and ‘cold’) and temperature, overlooking the transfer of heat energy between
objects at different temperatures, and not realising that ‘hot’ and ‘cold’ sensations
are at the opposite ends of a continuum. These findings are consistent with
studies from other countries that used qualitative research methods. This
finding illustrates the utility of the TCE questionnaire in large-scale studies.
The Variables That Influence Students’ Thermal Conceptual Understanding
Conceptual understanding related to the four conceptual groups was found to be
influenced by students’ years of schooling, the subjects currently studied and pre-
viously studied physics topics about thermal energy. However, the influences were
limited to certain conceptual groups and also, the strengths of impact were weak,
even though the influences of school years and previous studied physics topics were
significant. Two findings have emerged from this study:
(1) The influence of students’ school years was limited to the heat transfer and temp-
erature changes and heat conductivity and equilibrium conceptual groups, but
the impact of school years on conceptual understanding in these two groups
was small. However, the currently studied science subjects had a large influence
on the heat, transfer and temperature changes as well as melting and freezing con-
ceptual groups in this research, but had a very limited impact on the heat conduc-
tivity and equilibrium conceptual group.
(2) Most of the previously studied physics topics significantly influenced thermal
conceptual understanding in all conceptual groups except the boiling conceptual
group. The reason was that the boiling concept in the TCE questionnaire was
highly related to macroscopic understanding. Students first had to understand
boiling in the normal air pressure and then consider the microscopic understand-
ing of phase changes. However, according to Luera, Otto, and Zitzewitz (2006),
some item distracters in the TCE do not indicate which concepts students do not
understand. The heat topic did not have a significant influence on any of the con-
ceptual groups and the heating and cooling topic did not show any significant
influence on the boiling, melting and freezing conceptual group. Most topics
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had a moderate effect on the heat transfer and temperature change conceptual
group (eta squared values from 0.06 to 0.10). Most previously studied physics
topics had limited effect on the heat conductivity and the equilibrium group
except for the ‘phase changes’ topic that had a moderate effect (eta squared
value ¼ 0.07). Most physics topics that students had previously studied had
limited effect on the melting and freezing conceptual group (eta squared value:
0.01–0.04).
Implications
The findings of this study have several implications for classroom physics instruction
as well as for future research in physics education, especially in Korea. At a general
level, the outcomes of the study provide indicators to teachers and curriculum devel-
opers in their planning of classroom instruction based on the needs of students in
different achieving groups and science curriculum based on students’ understanding
in different contexts. Even though students displayed a better understanding when
they had more learning opportunities in school, several alternative conceptions
seemed particularly resilient to change, e.g. boiling water in normal conditions.
Korean students continue to do extremely well in the trends in international math-
ematics and science study (TIMSS) since 1995 (Martin, Mullis, & Foy, 2008). In the
Programme for International Student Assessment (PISA) 2006, Korean students
were also placed statistically significantly above the OECD average (OECD, 2007).
The TIMSS tests are directed towards year 8 and the PISA tests towards 15 years
old. Further TIMSS tests are more likely to include items based on the taught curri-
culum (such as items for asking scientific knowledge about knowing, applying and
reasoning) and it might be expected that the Korean students in this study would
perform well when the items are based on topics related to the taught curriculum.
As shown in Tables 2 and 3 (the boiling conceptual group and the heat conductivity
equilibrium conceptual group), this appears not to be the case with relatively low
response rates across all three years 10–12. As noted in the Introduction, the
Korean national curriculum has incorporated an STS emphasis and the constructivist
classroom has been emphasised and scientific literacy highlighted (Ministry of Edu-
cation, 1992a, 1992b, 1997). However, research about a decade ago showed that tea-
chers continue to maintain highly discipline-centred traditional teaching and provide
students with little experience of physics questions based on everyday life (Kim, 2001;
Kwon, 2001; Oh & Kim, 2001). The teachers in this sample would appear to be con-
tinuing with this same style of teaching. Consequently, this study has provided an
important baseline as to how well Korean students answer questions based on every-
day phenomena related to thermal concepts and upon which further similar studies
can be based. Using the original TCE questionnaire, similar findings of conceptual
understanding difficulties in everyday contexts have been reported by Thai secondary
students (Kruatong, Sung-ong, & Jones, 2006), by Thai and Australian university stu-
dents (Georgiou, Sharma, O’Byrne, Sefton, & McInnes, 2009), and by university stu-
dents in the USA (Luera, Otto, & Zitzewitz, 2006).
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If the Korean Ministry of Education wishes to continue with an emphasis on STS
and the constructivist classroom highlighting scientific literacy, it may be useful to
examine the context-based curricula with extensive student materials developed in
England, the Netherlands, USA, and Germany, beginning almost 30 years ago
(Nentwig & Waddington, 2005). In research studies, the comparison is between stu-
dents’ achievement in the traditional course with a context-based course at the end of
the secondary school examination. A review of such comparisons by Bennett,
Lubben, and Hogarth (2007) showed higher achievement in context–based
courses, but with a note that the teachers involved in these courses are interested
and deem the courses to have potential benefits to their students. However, in
reviews of these context-based courses, there is no commentary of the types of ques-
tions in the examinations. Indeed, evaluation of student achievement using context-
based items seems to be less well developed and reported than the curricula. We
suspect this is part of the explanation of the less than expected achievement of the
Korean sample on this study.
Further research is planned to analyse why students in years 10–12 have difficulty
in understanding or using these thermal concepts when applied in everyday life con-
texts. An open-ended questionnaire will be developed for which students will be
required to provide explanations for their selections of responses to the items and
student interviews will also be conducted. Recently conducted studies have shown
that conceptual tests can be effective tools for improving students’ conceptual learn-
ing (Chang, Yeh, & Barufaldi, 2010; Roediger & Karpicke, 2006). In keeping with
these recent findings, further research should be considered in evaluating the efficacy
of the TCE as a means of facilitating students’ understanding of thermal concepts in
everyday contexts. These students’ understanding can be used for the context-based
programme the development and the developing teaching materials for teachers.
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