The effect of the Case Stories on Pre-service Teachers? Understanding of Acid-Base Concepts

ÖRNEK OLAYLARIN FEN BİLGİSİ ÖĞRETMEN ADAYLARININ ASİT-BAZ KONUSUNU ANLAMASINA ETKİSİ

Abstract

Students’ attitudes, abilities and experiences influence their learning. Thus, as Ausubel (1968) stated that students’ preexisting knowledge is the one of the most important factors that affecting students’ learning. Shapiro (2004) mentioned that students’ existing knowledge is inadequate and students could not understand the concepts adequately. Shapiro also stated that students’ these understanding are also different than the scientific understanding and scientific knowledge. When student’ understanding of one concept is different from scientific understanding, it is stated that that student has a misconception. Misconception does not mean lack of knowledge and wrong description. Misconceptions appear at the end of the pre-existing knowledge and experiences related to that concept. Students having misconceptions could not make meaningful connections related to concepts and so it is difficult to eliminate misconceptions with traditional method. Because of misconceptions, students’ learning get difficult and so meaningful learning could not be occurred. Therefore, in order to eliminate students’ misconceptions and establish conceptual understanding, it is necessary for students to construct their knowledge. In order to use case-based learning in the classroom, teachers should firstly learn constructivist approach and its applications in the education faculties. Most of the courses in the education faculties are related to the properties of constructivist approach and its importance on learning. Also in some courses, in their own classroom with their peer or in real classroom with real students, pre-service teachers are doing microteaching in line with constructivist approach. However, other than education courses in education faculties, especially in content knowledge courses instructors generally use traditional approaches. However, it is important to use constructivist approach in these courses like chemistry, physics, and mathematics. The reason of this is that pre-service teachers could construct their knowledge and also the instructor could be the role model for pre-service teachers. Thus, the present is conducted on science pre-service teachers in general chemistry course. According to the most of the students, chemistry is considered as abstract and most students stated that it is difficult to understand chemistry concepts. One of the topics that students and pre-service teachers’ having misconceptions and difficult to understand were acid and bases topic. The other reason of studying with acid-base topic is that this topic is abstract, it is the one of the basic chemistry topics, it is related to the other chemistry topics (for example, matter, chemical equilibrium, chemical reactions, solubility). In addition to this, it is stated that the studies related to the development of conceptual understanding on acids and bases were generally conducted on secondary and university students and there is not much study on pre-service teachers. Thus, the participants of the study were freshmen pre-service science teachers. It is important to eliminate pre-service teachers’ misconceptions on acid and bases because pre-service teachers make meaningful learning and their future students understand this topic and future students could have lesser misconceptions. Thus, in the present study, pre-service teachers’ misconceptions related to acid and bases were eliminated by case-based learning and the development of knowledge in pre-service teachers was investigated deeply. The purpose of this study is to investigate the effect of case stories on pre-service teachers’ conceptual understanding. One of the strategies for developing conceptual understanding is constructivist approach. Case stories were prepared according to this approach. According to this approach, pre-service teachers were active and they construct their knowledge. Instructors guide the pre-service teachers. Constructivist approach covers the nature of science and how learning was implemented in the class. According to this approach, students construct their knowledge in to existing knowledge and this information is meaningful for him or her. Thus, students do not transfer the knowledge instead they construct the knowledge. There are some teaching methods that are using constructivist approach; one of them is case-based learning instruction. According to case-based learning instruction, students were active in the class; they have the responsibility for constructing their own knowledge. The role of teacher is to guide students while using cases. Case stories were prepared according to the constructivist approach and so pre-service teachers construct their knowledge. Case stories were presented to pre-service teachers as Herreid (1994) stated. Case stories were stories with a message and pre-service teachers analyzed the cases for considering the solutions the cases. Herreid (1994) stated that case-based learning could be implemented with four types. These are; lecturing, individual assignment, discussion and small group discussion. All four types of case-based learning, the properties of the cases were the same but the roles of teacher and students are different. Thus, in the present study, Herreid (1994)’s small group discussion was conducted and instructor and pre-service teachers work together and pre-service teachers analyzed the case stories with each other and they have control for analyzing the cases. In the present study, pre-service teachers were instructed with small group format because they could learn more from each other. This study was conducted on acid-base concept because many studies stated that this concept is difficult (Sheppard, 2006). In addition, acid-base concepts were abstract and this concept was one of the fundamental concepts of the chemistry and also this concept was related to the other concepts. This study is a qualitative study and this is a case study. In this study, pre-service teachers’ responses o

Özet

Bu çalışmanın amacı, Fen Bilgisi öğretmen adaylarının kimya konularındaki kavramsal anlamalarını örnek olaylarla geliştirmektir. Ayrıca, çalışmada öğretmen adaylarının örnek olaylara verdikleri cevaplar üzerinden kavramsal anlamaları hakkında bir değerlendirme yapılmıştır. Bu çalışma nitel bir çalışmadır. Öğretmen adaylarına bazı kimya konuları ile ilgili örnek olaylar sunulmuş ve onlardan cevaplarını belirtmeleri istenmiştir. Çalışma 72 birinci sınıf Fen Bilgisi Öğretmen adayı üzerinde gerçekleştirilmiştir ve altı hafta sürmüştür. Öğretmen adaylarının kavramsal anlamalarında meydana gelen gelişim onların örnek olaylara verdikleri cevaplarla belirlenmiştir. Çalışmanın sonucunda öğretmen adaylarının örnek olaylara verdikleri cevapların haftalar geçtikçe bilimsel anlamda geliştiği, derslere daha aktif olarak katıldıkları görülmüştür. Öğretmen adaylarına dersi nasıl anlatılmasını istedikleri sorulduğunda pek çoğu örnek olay yöntemini sevdiğini belirtmiş, sebebi olarak da öğrendikleri somut kimya konularının günlük hayattaki karşılıklarını görmenin heyecanlı olduğunu belirtmişlerdir. Sonuç olarak, örnek olay yöntemi öğretmen adaylarının asit-baz konusunun kavramsal anlaması üzerinde etkili olduğu gözlemlenmiştir. Bu sonuçlarla, Fen Bilgisi Öğretmenliği programlarında okutulan Genel Kimya derslerinde bu yöntemin uygulanabileceği önerilmektedir.