Cette thèse explore les ressources cognitives que mobilisent des élèves ingénieurs dans un APP (Apprentissage par problème) dans une tâche de conception d'un objet technique. La situation-problème à laquelle ces élèves sont confrontés est constituée par un système technique inédit de réfrigération sans apport extérieur d'énergie. Dans cet apprentissage, les élèves doivent concevoir l'objet technique et apprendre des concepts en thermodynamique. Deux groupes d'élèves sont comparés : le premier dispose d'un modèle analogique d'une situation connue pour aborder la situation nouvelle, le second ne dispose que du texte. Les questions de recherches : Que construisent ces élèves comme connaissances ?Qu'apportent ces deux types d'apprentissage (l'apprentissage par une situation connue et l'apprentissage par le texte) ? Quels sont les obstacles que rencontrent ces élèves ? Les hypothèses : un apprentissage par une situation connue conduit à la construction de connaissances opératives (des concepts outils). Un apprentissage par le texte conduit à la construction de connaissances décontextualisées (des concepts objets). Un apprentissage par les situations dans un dispositif didactique conduit ultérieurement à la construction de concepts catégoriels. Ces deux types d'apprentissage impliquent l'obstacle épistémologique dans la construction des concepts dans leurs deux fonctions : outil et objet.

The purpose of this study was to investigate the difficulties encountered by the grade ten township learners with respect to the concept of electricity. More specifically, the study attempted to explore the learners’ scientific knowledge by investigating their conceptions or alternative conceptions about electricity; the influence of learners’ age, career interests and gender issues on their conceptions of electricity and; the effectiveness of concept mapping (a pedagogic tool designed by Novak in the 1970s) in facilitating the learners’ understanding of electricity. The study was premised on socio-cultural constructivism as well as meaningful learning as espoused by Ausubel (1968). A Pre-Test-Post-Test Control Group Design was adopted in the study in which two comparable groups were used. The data was analyzed using both qualitative and quantitative research methods and the instruments that were used included a conception of electricity (COET) (originally adopted and administered in the Western Cape, Northern Cape provinces and in Norway in 1999 for the purpose of Science and Technology Literacy Project (STLP) with the hope that their reliability and validity was guaranteed); selected learner interviews and evaluation forms. The summary of findings has suggested that the Grade ten learners held misconceptions about the concept of electricity even after they were exposed to intervention that included concept mapping. In terms of the gender issues, there was no significant difference in performance between the boys and girls though the females outperformed their male counterparts at both groups. The underachievement of the older learners compared to the younger ones has also surfaced and that is against expectation since a number of studies carried out earlier (see Ogunniyi (1999)) have already corroborated such findings. With respect to career interests, what the learners indicated as their future dreams, i.e. what they intend to do and become, seems to have been influenced their performance at the pre- and post-test stages. / Magister Educationis - MEd

<p><font size="3"> <p>The purpose of this study was to investigate the difficulties encountered by the grade ten township learners with respect to the concept of electricity. More specifically, the study attempted to explore the learners&rsquo / scientific knowledge by investigating their conceptions or alternative conceptions about electricity / the influence of learners&rsquo / age, career interests and gender issues on their conceptions of electricity and / the effectiveness of concept mapping (a pedagogic tool designed by Novak in the 1970s) in facilitating the learners&rsquo / understanding of electricity. The study was premised on socio-cultural constructivism as well as meaningful learning as espoused by Ausubel (1968). A Pre-Test-Post-Test Control Group Design was adopted in the study in which two comparable groups were used. The data was analyzed using both qualitative and quantitative research methods and the instruments that were used included a conception of electricity (COET) (originally adopted and administered in the Western Cape, Northern Cape provinces and in Norway in 1999 for the purpose of Science and Technology Literacy Project (STLP) with the hope that their reliability and validity was guaranteed) / selected learner interviews and evaluation forms. The summary of findings has suggested that the Grade ten learners held misconceptions about the concept of electricity even after they were exposed to intervention that included concept mapping. In terms of the gender issues, there was no significant difference in performance between the boys and girls though the females outperformed their male counterparts at both groups. The underachievement of the older learners compared to the younger ones has also surfaced and that is against expectation since a number of studies carried out earlier (see Ogunniyi (1999)) have already corroborated such findings. With respect to career interests, what the learners indicated as their future dreams, i.e. what they intend to do and become, seems to have been influenced their performance at the pre- and post-test stages.</p> </font></p>

<p><font size="3"> <p>The purpose of this study was to investigate the difficulties encountered by the grade ten township learners with respect to the concept of electricity. More specifically, the study attempted to explore the learners&rsquo / scientific knowledge by investigating their conceptions or alternative conceptions about electricity / the influence of learners&rsquo / age, career interests and gender issues on their conceptions of electricity and / the effectiveness of concept mapping (a pedagogic tool designed by Novak in the 1970s) in facilitating the learners&rsquo / understanding of electricity. The study was premised on socio-cultural constructivism as well as meaningful learning as espoused by Ausubel (1968). A Pre-Test-Post-Test Control Group Design was adopted in the study in which two comparable groups were used. The data was analyzed using both qualitative and quantitative research methods and the instruments that were used included a conception of electricity (COET) (originally adopted and administered in the Western Cape, Northern Cape provinces and in Norway in 1999 for the purpose of Science and Technology Literacy Project (STLP) with the hope that their reliability and validity was guaranteed) / selected learner interviews and evaluation forms. The summary of findings has suggested that the Grade ten learners held misconceptions about the concept of electricity even after they were exposed to intervention that included concept mapping. In terms of the gender issues, there was no significant difference in performance between the boys and girls though the females outperformed their male counterparts at both groups. The underachievement of the older learners compared to the younger ones has also surfaced and that is against expectation since a number of studies carried out earlier (see Ogunniyi (1999)) have already corroborated such findings. With respect to career interests, what the learners indicated as their future dreams, i.e. what they intend to do and become, seems to have been influenced their performance at the pre- and post-test stages.</p> </font></p>

This study was designed to identify ninth grade students&amp / #8217 / misconceptions about static electricity concept and to determine relationship among students&amp / #8217 / gender, socio-economic status, interest, experience with students&amp / #8217 / misconceptions about static electricity. For this study, Static Electricity Concept Test (SECT) and Socio-Economic Status, Interest and Experience Questionnaire about Static Electricity (SESIEQ) were developed to assess students&amp / #8217 / misconceptions related to static electricity and their socio-economic status, interest and experience about static electricity, respectively. This study was carried out during 2002-2003 spring semester with 1260 ninth grade students from 9 Anatolian and regular high schools in &Ccedil / ankaya and Mamak districts of Ankara. Findings of the concept test indicated that many students had misconceptions about static electricity. Negative and significant relationships among students&amp / #8217 / gender, socio-economic status, interest, experience and misconception scores were found. The difference between misconception scores of male and female students was significant in favor of males. However, when the data were analyzed using ANCOVA while controlling students&amp / #8217 / socio-economic status, interest in static electricity and experience about static electricity, no difference was observed between the misconception scores of male and female students.

This study developed the software named as &ldquo / Physical World&rdquo / which is a virtual laboratory program focusing on Newtonian Physics, which supports two modes called the &ldquo / studying by observation&rdquo / and &ldquo / studying by programming&rdquo / . In &ldquo / studying by observation&rdquo / mode, the motion is calculated due to equations known by the computer. And in &ldquo / studying by programming&rdquo / mode, students write equations of motion and the computer calculates motion due to those equations. A total of six high school second grade students studied force and motion concepts, using Physical World with assistance of one instructor, six hours each. Two of the students studied with &ldquo / studying by observation&rdquo / , two of the students studied with &ldquo / studying by programming&rdquo / , and two of the students studied with use of both of the modes. All students received a test with 10 items chosen from FCI as a pretest and received the same test as a posttest. Students&rsquo / test results were examined to find effects of Physical World&rsquo / s two modes and use of both of the modes over misconceptions about physics. Their actions and responds were examined to find Physical World&rsquo / s effects on scientific thinking for each of the three groups. Four specialists from related fields examined the software and filled evaluation forms and stated feedbacks. From the responds of students during the studies, evidence of positive effect of using the &ldquo / studying by programming&rdquo / mode on scientific thinking was found. And evidence of positive effect of using both modes on misconceptions was found.

The aim of this study is to investigate the views of preservice science teachers on nature of science (NOS). A total of 166 preservice science teachers participated in the study. A 21-item &ldquo / Views on Science-Technology-Society (VOSTS)&rdquo / instrument, translated and adapted into Turkish, were utilized to assess participants&rsquo / views on the nature of science. The VOSTS (Aikenhead, Ryan and Fleming, 1989) is a pool of 114 empirically developed multiple-choice items with nine categories. In this study, 21 item selected from the epistemology of science category corresponded to the purposes of the assessment. In order to understand participants&rsquo / views on nature of science in depth, semi-structured interviews were also conducted by 9 volunteer preservice science teachers. The results gave a picture of the preservice science teachers&rsquo / views on nature of science. Results of this study revealed preservice science teachers&rsquo / misconceptions on nature of science. Their views are mostly traditional on the nature of science. Results of the study indicated that preservice science teachers held traditional views (naive) regarding the definition of science / the nature of scientific models / the relationships between hypotheses, theories, and laws / fundamental assumptions for all science / the scientific method / uncertainty in scientific knowledge / epistemological status of scientific knowledge / coherence of concepts across disciplines. On the other hand participants have contemporary views (realistic) on the nature of observation / the nature of classification schemes / the tentativeness of scientific knowledge / cause and effect relationship. Analysis of interviews also supported these findings and gave a deep insight on preservice science teachers&rsquo / views on nature of science.

The purpose of this study was to investigate the effects of 5E learning cycle, conceptual change texts and traditional instruction on 8th grade students&amp / #8217 / understanding of photosynthesis and respiration in plants. Besides, the effect of instruction on students&amp / #8217 / attitudes toward science as a school subject was investigated. One hundred and one, 8th grade students from three classes of one elementary school in Ankara attended in this study. This study was carried out during the fall semester of 2003-2004 academic year. The classes were randomly assigned as control and experimental groups. Students in the first experimental group (n=33) received 5E learning cycle based instruction, the second experimental group (n=34) received conceptual change text based instruction and students in the control group (n=34) received traditional instruction. Two-tier multiple-choice diagnostic test, Photosynthesis and Respiration in Plants Concept Test, was used to determine students&amp / #8217 / understanding of photosynthesis and respiration in plants. The test was administered to the sample of the study as pre- and post-test. Students&amp / #8217 / attitudes toward science and their reasoning abilities were measured by Attitude Scale Toward Science and Test of Logical Thinking respectively. The hypotheses of the study were tested by using analysis of covariance (ANCOVA). The results indicated that there were significant differences among the treatment groups with respect to their understanding of photosynthesis and respiration in plants. Both 5E learning cycle based instruction and conceptual change text based instruction were found effective to eliminate 8th grade students&amp / #8217 / misconceptions about photosynthesis and respiration in plants. The results also showed that there were no significant differences among the treatment groups with respect to attitudes toward science as a school subject.

The main purpose of this study was developing a three-tier test for assessing 11th grade students&rsquo / misconceptions about geometric optic. The accessible population was all 11th grade science students in Bayrampasa, Istanbul. While developing the test, interviews and open-ended tests were used to collect data to create the three-tier test. An interview questionnaire was developed based on the literature review. 15 11th grade students were interviewed by this questionnaire. Then, an open-ended test was created based on the interview results and also the literature review. It was applied to 114 11th grade science students. The responses of the students for each item were categorized considering the frequencies. Then, these categories were used in the development of the Three-tier Geometric Optic Misconception Test (TTGOMT). The categories were used as the distracters of the items in the TTGOMT. Besides, some of the distracters were extracted from the interview results and the literature review even if they had no frequencies in open-ended test results. The test was applied to the 141 11th grade high school students. A factor analysis was conducted to establish the content validity of the TTGOMT and five categories were found. Also, the proportions of the false positives and false negatives were estimated to establish the content validity and found 28.2 % for the false positives and 3.4 % for false negatives. The construct validity was established by estimating a correlation between the scores of the students for the first two tiers and confidence levels for the third tier. Two reliability analyses were conducted by using Cronbach alpha. One of the reliability analyses was estimated based on the correct answers of the students for all the three tiers together and found 0.55. The other one was estimated based on the misconceptions of the students and found 0.28. Moreover, item analysis was done for each item by using Iteman program.

The purpose of this study is to develop a three-tier test for assessing high school students&rsquo / misconceptions concerning force and motion. The first tier is a traditional multiple choice item, the second tier presents several alternatives addressing the reason for the response for the first tier, and the third tier asks if examinees are confident for their responses to the first two tiers. In the process of test development, Force and Motion Test Requesting Reasoning was developed and utilized to determine the alternatives of Force and Motion Three Tier Test (FMTTT). The test was administered to 207 students, but 19 students were removed from all analyses due to too many missing items. For checking validity of the FMTTT, correlation was investigated between confidence levels and student scores on the first two tiers, and also correlation between confidence levels and student misconception scores on the first two tiers was investigated. Factor analyses were conducted using scores and misconception scores / and percentages of false negatives and false positives were estimated. The percentages of false negatives and false positives were found to be 6% and 8%, respectively. The reliability coefficients were estimated for student scores and misconception scores as 0.48 and 0.62, respectively. In conclusion, using the FMTTT as an achievement test may not be as reliable as using it as a misconception test.