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Asia-Pacific Forum on Science
Learning and Teaching, Volume 5, Issue 1, Article 1 (Apr., 2004) Salih ÇEPNİ, Tuncay ÖZSEVGEÇ and Lale CERRAH Turkish middle school students'cognitive development levels in science
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Asia-Pacific Forum on Science
Learning and Teaching, Volume 5, Issue 1, Article 1 (Apr., 2004) Salih ÇEPNİ, Tuncay ÖZSEVGEÇ and Lale CERRAH Turkish middle school students'cognitive development levels in science
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Method
Developing and validating the instrument
In order to diagnose the cognitive development of children, Piaget pioneered the one-to-one clinical interview. Administering the Piagetian tasks individually has traditionally been recognized as the preferable method for assessing the formal reasoning abilities of an individual. Because of the difficulty of standardizing the methods employed by several interviewers, this technique is not objective (Tschopp & Kurdek, 1981; Ahlawat & Billeh, 1987), and it requires experienced interviewers, significant budgets, and special materials and equipments. In addition, it is too time-consuming and, not objectively and easily assessed (Lawson, 1978). Therefore, a number of authors have considered developing open-ended and structured tests related to cognitive development which can be used to assess individuals in groups of 20 or more at one time (Shayer, Adey & Wylam, 1981). If one's concern is to estimate subjects' optimum level of thinking, group tests may offer further advantages for gathering data from large samples. Besides, they can be at least as valid as, and may be more reliable than clinical interviews. In this study, a group format test was used.
Firstly, a science cognitive development test (SCDT) covering motion and energy units in the middle school science curriculum, consisting of 30 questions, was prepared to determine students' logical development by taking into consideration the characteristic of the Piaget's concrete and formal operational stages. After developing questions, six experts in science education independently examined each question to check whether it is suitable in terms of characteristics of the developmental levels. If 95% of the experts agreed on an item, this item was put on the SCDT. Further, five middle school science teachers examined deeply the test's reading ability and appropriateness of the items for their instructional program. In this way, SCDT's content and validity was assured. The first SCDT consisted of two subtests. One subtest consisted of 10 questions involving concrete operational abilities. Another subtest comprised 20 questions involving formal operational abilities.
Two pilot studies were carried out for the SCDT. In the first pilot study, reading ability was tested with 30 seventh middle school students and item analysis was done. The number of test questions was reduced from 30 to 27. A second pilot study involved another 35 seventh middle school students who ranged in age from 133 to 151 month. The mean age = 4.39 month. In the process of second pilot study item analysis was done again and the final SCDT consisted of total 22 questions.
Finally, the SCDT's reliability coefficient was calculated (r = 0.66). Saunders & Shepardson, (1987) developed a cognitive test to determine student's thinking ability and found a reliability coefficient (r = 0.63). They stated that their reliability coefficient indicated that the test was sufficient to determine student's thinking abilities. In this respect, our reliability coefficient is capable of determining students' cognitive development.
The final SCDT (see Appendix) comprises of 22 science context questions. The first 20 questions were multiple choice and the 21st and 22nd questions are open-ended. The concrete operational part consists of 7 questions: seriation, 3 questions; classification, 2 questions and conservation, 2 questions. The formal operational part comprises 15 questions: probability reasoning, 5 questions; proportional reasoning, 1 questions; combinatorial reasoning, 2 questions; correlational reasoning, 2 questions; controlling variables, 2 questions and hypothetical reasoning, 3 questions.
Copyright (C) 2004 HKIEd APFSLT. Volume 5, Issue 1, Article 1 (Apr., 2004). All Rights Reserved.
