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Asia-Pacific
Forum on Science Learning and Teaching, Volume 6, Issue 2, Article 2
(Dec., 2005) Sabri KOCAKULAH, Evrim USTUNLUOGLU and Aysel KOCAKULAH The effect of teaching in native and foreign language on students' conceptual understanding in science courses
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Findings
Findings of the conceptual understanding test are presented quantitatively and qualitatively. In quantitative findings, responses given to four-open ended questions by the two groups of students were analysed in percentages. In qualitative analysis, responses to open-ended questions were interpreted conceptually.
Quantitative Findings
The findings are presented and discussed separately question by question.
Table IV. Distribution of Students' Responses in Conceptual Understanding Test.
Scientifically Acceptable Arguments Skier Question Clockwork mouse Question Porter Question Compressed Spring Question Ss1 Ss2 Df* Ss1 Ss2 Df Ss1 Ss2 Df Ss1 Ss2 Df Full Argument 2.80 11.21 8.41 9.34 10.28 0.94 4.67 16.82 12.15 9.34 22.43 13.09 Part of Argument 3.74 14.02 10.28 32.71 47.67 14.96 13.08 13.08 0.00 12.15 30.84 18.69 Scientifically Unacceptable Arguments 18.69 15.90 12.15 31.78 Response Related to Energy 26.17 14.95 11.22 41.13 29.90 11.23 63.55 53.27 10.28 40.20 35.51 4.69 Response Related to Other Inappropriate Ideas 61.68 54.21 7.47 9.34 6.54 2.80 16.83 14.96 1.87 25.23 5.61 19.62 Uncodeable Responses 4.67 4.67 0.00 6.54 3.74 2.80 1.87 1.87 0.00 10.28 5.61 4.67 No Response 0.94 0.94 0.00 0.94 1.87 0.93 0.00 0.00 0.00 2.80 0.00 2.80 *Df: shows the difference between Ss1 and Ss2
Analysis of the Skier question:
Skier question (see Appendix) was to evaluate comprehensibility level of concepts concerning "transfer of energy" , "kinetic and potential energy" (see Figure 1). The results showed a difference of 18.69% in favour of Ss2. This shows that those who studied the science course in the native language were capable of giving more scientifically acceptable explanations than those who studied in the foreign language (see Table IV).
Analysis of the Clockwork mouse question:
Clockwork mouse question (see Appendix) is related to the concepts of "transfer of energy" and "potential energy of a spring" and aims to evaluate students' ability to synthesize. As Table IV clearly shows that the difference between the percentages of the students at both schools who gave full arguments has decreased to 0.94%. On the other hand, the difference between the two groups regarding the scientifically unacceptable responses concerning "the concept of energy" has been found to be 11.23%, which shows that more Ss1 lack the ability to use coherent conceptual explanations related to energy than Ss2. The results also indicated that 9.34% of Ss1 and 6.54% of Ss2 gave scientifically wrong responses. A difference of 2.80% can be interpreted as showing that Ss1 have more misconceptions and difficulties in explaining the question than Ss2 do.
Analysis of the Porter question:
Students were asked to give an explanation of the concept of "potential energy" based on mass, height and gravitational acceleration. The analysis of the Porter question (see Appendix) shows that 16.82% of Ss2 answered this question correctly as opposed to only 4.67% of Ss1. There has been no difference found between the two schools concerning scientifically acceptable and partly correct responses. The striking point, in view of the results, is the difference between the percentages of the two groups of students who gave scientifically unacceptable responses. While the percentage of Ss2 who used the concept of energy but scientifically wrong is 53.27%, the percentage of Ss1 is 63.55%. A difference of 10.28% indicates that Ss1 had more misconceptions concerning "energy" than Ss2 had. Furthermore, it is seen that the number of Ss1 giving wrong explanations unrelated to energy is more than the number of Ss2 (1.87%).
Analysis of the Compressed spring question:
Compressed spring question (see Appendix) aims to evaluate comprehensibility of "kinetic energy", "potential energy of a string", "heat energy" and "frictional force" by the two groups of students. It is striking that more Ss2 gave completely correct and partially correct responses than Ss1 did (31.78%). In addition, it should be noted that percentage of scientifically unacceptable responses given by Ss1 is also higher than the percentage given by Ss2 (24.31%).
Quantitative findings show that students at the English medium school gave more scientifically unacceptable arguments than students at the native language school. The following section covers qualitative findings in detail related to students' responses at both schools.
Qualitative Findings
This section examines samples of misconceptions. First, responses were categorized for each question in the conceptual understanding test. Analysis revealed that Ss1 used quite different concepts related to the questions. This situation yielded the fact that more response categories were given by Ss1 than were given by Ss2, which might demonstrate that Ss1 had more misconceptions than Ss2 did. Second, each category was examined in detail and common misconceptions were identified. This process was particularly important for the researchers to bring up the matter of difficulties in learning since those misconceptions were used in all responses by many students. Table V shows some of the striking misconceptions given to the questions by students.
Table V. Common Misconceptions Identified in Students' Responses
Ss1(%) Ss2(%) An object can't continue moving if there is no friction force 30.84 28.03 It is necessary to give an object power in order to set it in motion 36.45 19.63 When compressed, a spring has kinetic energy 28.03 14.95 An object has to stop in order to have potential energy 42.06 30.84 Only the objects at a certain height from ground have potential energy 44.86 40.19 Motionless objects do not have energy 37.38 28.03 Gravity reduces the energy which an object has. If there is gravity, there is energy loss 12.15 11.21 Objects always have potential energy 23.36 19.63 Potential energy which an object has before starting moving is more than its kinetic energy it has at the final stage of motion 17.76 14.95 Table V briefly indicates that Ss1 have more misconceptions than Ss2. Particularly the difference between two groups increases in response categories in which there are misconceptions that can be attributed to the effect of language. To illustrate, the rate of Ss1 (36.45%) stating that "it is necessary to give an object power in order to set it in motion" is more than the rate of Ss2 (19.63%). It is interesting to note that students used the concept of "power" instead of "energy". The following excerpt proves how the concept of "energy" becomes identical with the concept of "power".
"When Ayse winds up her clockwork mouse, she gives power to it. While the clockwork mouse is moving, its energy is reduced with friction; it has no power when it stops" (from student 106)
It is also interesting to note that students often used "force", "acceleration", "velocity" instead of the concept of "energy". For example, some Ss1 (20.56%) used expressions such as "Energy=Force x Distance" and "energy equals to work". As indicated in Table V, 28.03% of Ss1 and 14.95% of Ss2 confused "potential energy" with "kinetic energy" and explained the question related to the compressed spring as follows:
"spring has kinetic energy when it is compressed" (from student 22)
Table V indicates that students have many misconceptions about "potential energy". The idea that an object has to stop in order to have potential energy was accepted by 42.06% of Ss1 and 30.84% of Ss2. Students at English medium instruction school (44.86%) and students at native language instruction school (40.19%) thought that only the objects at a certain height from ground have potential energy. Moreover, 23.36% of Ss1 and 19.63% of Ss2 explained that objects always have potential energy. Compared to Ss2, more Ss1 (37.38%) stated that motionless objects do not have energy. In the case of clockwork mouse question, students reasoned that the clockwork mouse's energy would depend on its movement, in the sense that the clockwork mouse would only have energy when moving, or would have the most energy when moving.
The reasons why students have many misconceptions related to potential energy, transfer of energy, conservation of energy, and frictional force are explained with samples as below:
Responses Including Unacceptable Ideas about Potential Energy
Students should know the concept of "potential energy" in order to explain the situations given for the questions of 1, 2 and 4. However, it is seen that both groups of students had difficulty in explaining the concept of "potential energy". Ss1 attributed different meanings to "the concept of potential" due to its meanings in foreign language. The concept "potential" was explained by many students as an energy already existing in the structures of objects. This misconception might have stemmed from the dictionaries that students used. When defined in dictionaries, the word "potential" is explained as "power; force, potential as existing in possibility; not at present active or developed, but able to become so".
Samples of answers by Ss1 about potential energy are outlined below. For instance, 20 students responded the question by using a similar explanation;
"Skier has potential energy as long as he does not move" (an example from student 72)
while 19 students referred to potential energy such as:
"A clockwork mouse has potential energy when it is not moving. Potential energy is transferred into kinetic energy when it moves. That is, it consumes more energy and it has only potential energy when it stops." (an example from student 93)
As indicated in Table V and in students' responses, Ss1 do not have scientifically acceptable ideas about when and how potential energy is used.
Responses Indicating the Lack of Understanding about the Transfer of Energy
The students were asked to explain "how one form of energy is transferred into different form?" which related to questions 1, 2 and 4. Ss1 gave variety of explanations concerning those questions compared to the Ss2. Particularly the concepts they used in their responses indicated diversity. It was seen that Ss1 often used "release of energy", "degradation of energy" and 'the waste of energy" instead of using 'transfer of energy". The following explanation given by student 91 is an example of the lack of understanding about 'transfer of energy":
"A clockwork mouse has state energy while motionless. After it stops moving, and while it is motionless, it still has state energy. When Ayse winds up the mouse, it has got potential energy. When the potential energy is consumed, the potential energy of mouse is ready to turn into kinetic energy. When the mouse starts moving, kinetic energy is released and it has the highest energy in this state"
Another student who could not explain the transformation of energy from one form into different form gave the following explanation;
"Before Ayse winds up the clockwork mouse it has no energy. While winding up the clockwork mouse, some of Ayse’s energy passes through the clockwork mouse" (an example from student 48)
In this example, the student thinks that the transfer of energy is the transmitting of energy from one form (Ayse) to another (the clockwork mouse) without any change. In fact, the answer should have indicated that Ayse's energy is transferred to the clockwork mouse as potential energy.
Situations in Which Conservation of Energy is Considered as Conservation of Velocities
While answering the Skier question, students were expected to consider that total energy is conserved during transformation and that the energy is changed into a different form.
Responses concerning conservation of energy reveal that both groups had difficulty in explaining "the transfer of kinetic energy and potential energy". In frictionless systems, however, Ss1, attributed the source of kinetic energy (which objects have due to motion) only to the concept of velocity (which objects inherently have). Ss1 students thought that the kinetic energy of those objects was already formed at the moment of movement due to their intrinsic velocities they already had instead of thinking that the objects had potential energy. They explained conservation of energy as conservation of velocity. The following example is given to indicate how 20 students in the Ss1 group used the term "velocity" instead of 'kinetic energy".
"Murat will lose velocity while skiing down from hill A and climbing up hill B. He will start climbing up at hill C with the help of gained velocity while skiing down at hill B. But, his speed will be zero before he comes to summit C due to gravity and he will start skiing back. He will ski reversely, with gained velocity at hill C, but he will be unable to reach the summit of hill B since his velocity again comes to zero." (an example from student 12)
This explanation proves that the student ignored the concepts of "potential energy and kinetics energy" and conservation of energy was explained through the speed change of the object in motion. It is certainly possible to explain the change of kinetic energy which an object has by considering the change of its speed. However, it is interesting to note that the student did not mention the word "energy". Briefly, it was stated that what changed during movement was not energy, but speed and that conservation of energy was conservation of speed.
Situations in Which Frictional Force is not Understood
It was found that students gave scientifically unacceptable answers using the concept of frictional force for the first and fourth questions even though those questions were not directly related to frictional force. When the responses are examined, Ss2 think that there will not be an action impeding the motion in situations in which there is an absence of frictional force. This is a scientifically acceptable explanation even though it does not take part in the full argument part of the student responses. On the other hand, Ss1, attributing an opposite meaning to the frictional force, stated that frictional force was a kind of force that maintains motion and motion can not be maintained without the existence of this force.
The following examples are among the typical answers which are given by 16 Ss1 students;
"When there is no friction, the skier does not move, because there must be a frictional force between the ski and snow in order to push the ski". (an example from student 108)
"The skier has to stop after a while due to lack of friction, because speed increases only in case of frictional effect" (an example from student 84)
or
"If there was a friction between ski and snow, the skier could climb over the hill" (an example from student 81)
As seen in the extracts, although Ss2 fully comprehended the concept of "frictional force" , Ss1 have understood the opposite of what is actually true. This may be given as a concrete example which shows the effect of a foreign language on conceptual understanding.
Copyright (C) 2005 HKIEd APFSLT. Volume 6, Issue 2, Article 2 (Dec., 2005). All Rights Reserved.
