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Asia-Pacific Forum on Science Learning and Teaching, Volume 15, Issue 2, Article 6 (Dec., 2014) |
Data were collected in the Fall 2008 semester in which participants were enrolled in the course of Teaching and Learning General Science 1 at Bahrain Teachers College, University of Bahrain, Kingdom of Bahrain. This course was designed as part of the one-year PGDE programme for pre-service science teachers. The course focused on approaches for teaching general science and includes explicit-reflective activities that emphasize constructivist-inquiry-based instruction to help pre-service science teachers improve their and their students’ views of the NOS (Akerson & Hanuscin, 2007). In the same semester, pre-service science teachers took Teaching and Learning Biology 1 and Teaching and Learning Chemistry 1.
25 pre-service science teachers (24 female and 1 male) were participated to the study. Six of them (5 female and 1 male) volunteered to participate in interviews. None of the 25 participants had taken any courses or course work related to the NOS before they started PGDE programme. They stated that this course was the first course in their educational life that explicitly taught the concept of the NOS.
A three-hour workshop was also conducted by the author to the same class on the NOS in spring 2009. The workshop was videotaped and their work in the workshop was analyzed in terms of some aspects of the NOS (Figure 1).
Figure 1. Aspects of the NOS
The instructional approach-intervention
I developed and implemented an explicit-reflective non-context based approach to the NOS teaching for a science method course. Pre-service science teachers were engaged in two activities taken from the literature (Lederman, & Abd-El-Khalick, 1998; McComas, 1998) that were selected according to the instructional approach. The Puzzle Activity and The Trick Tracks Activity were purposely selected to introduce and reinforce to pre-service science teachers’ understanding of the main aspects of the NOS. These activities can be found on Internet Web sites and in books as an explicit-reflective instructional approach to the NOS (McComas, 1998; Akerson, Abd-El-Khalick, & Lederman, 2000). In teacher education, reflective approach is the usage of reflections for the personal and professional development of teachers (Rosenthal, 1991). Students can reflect on their understanding and articulate and elaborate their acquired NOS understanding.
The Puzzle Activity (Choi, 2004) is about getting the students to think about the nature of science, and also, showing the importance of being an active participant in the learning process. Students know the definition of science based on the out-dated Baconian view, but they should realize that science is dynamic, it is hands-on and minds-on, and it changes as our knowledge of the world increases.
The procedure for this activity is as follows: Pre-service science teachers are given all the pieces except the small square marked X (Figure 2b). Each piece represents current scientific data. Once the pre-service science teachers are given the pieces, no further instruction should be given; most pre-service science teachers will begin to arrange the pieces on their own. In a short amount of time, the pre-service science teachers will put the pieces together to make a square easily. After the pre-service science teachers have arranged the pieces to produce Figure 2a, the small square marked X is given to each student and explain that a new scientific discovery has been made. The pre-service science teachers must someway incorporate this new information to their puzzle. Students should be encouraged to work individually at first, and then, to work in groups if they are still struggling to put the pieces together. You should not allow them to share their arrangements at this stage. If one gets the correct arrangement, have that student cover up the answer. Group discussion and class discussion are encouraged during the second part of this activity to have their reflections on how they solved the puzzle and what procedures they followed. In addition, you can ask students to reflect on how scientists work and solve the problems that they confront. The pre-service science teachers’ work with regard to the puzzle activity is shown in Figure 2 a and b.
(a) (b) Figure 2(a), (b). Pre-service science teachers’ work on the puzzle activity
The Tricky Tracks activity (Lederman, & Abd-El-Khalick, 1998) was purposely selected to introduce and reinforce the pre-service science teachers’ understanding of the main aspects of the NOS. This activity conveys to students the message that there is no a single ‘correct’ answer. Based on the same set of data (observations), several valid answers to the same question can be obtained. The goal of the activity is to help students distinguish between observation and inference. The procedure for this activity is as follows: 1) students are shown foot print 1 and asked what they observe. Students immediately tell their inferences like “bird tracks or big bird and small bird tracks or necklace” without knowing that their descriptions are inference. 2) Students are shown foot prints 2 and 3 to discuss further observation and inference. This activity is well designed to discuss the difference between observation and inference. It provides an opportunity for students to understand the difference between observation and inference and reflect on the way in which scientists work. It illustrates how scientists might reach several valid answers to the same question based on the same set of observations or data.
A workshop was conducted in the second semester for three hours to enhance the pre-service science teachers’ understanding of the aspects of the NOS through explicit-reflective instruction. Examples of several hands-on and minds-on activities taken from the literature follows (all activities were used to find out the pre-service science teachers’ views on certain aspects of the NOS and to reinforce their understandings of the NOS aspects):
1. The cube activities (Lederman, & Abd-El-Khalick, 1998) (imagination, creativity, human inference): This activity focuses on scientific knowledge being based on human inference, imagination, and creativity. Scientists often look at the data they collect for certain patterns or regularities, as illustrated in this activity (it has certain patterns and regularities). Scientists then extrapolate their data in order to provide predictions for future behavior of the physical phenomena that they have been investigating based on the patterns and regularities.
The procedure for this activity is that students are divided into small groups and given several cubes that have different patterns. They can see all the sides of the cube except the bottom side. They are asked to find out what is on the bottom side of the cube. For example, on one cube consecutive consonant letters of English alphabet make meaningful words, so one group of the pre-service science teachers’ work on finding out the word on the bottom of the cube; please see Figure 3 and 4, respectively. BAT and CAT, FAT and HAT, and MAT and PAT..
Figure 3. Pre-service science teachers’ work on the cube activity
Figure 4. Pre-service science teachers’ work on the cube activity
2. Young? Old? Activity (Lederman, & Abd-El-Khalick, 1998) (science as theory-laden and subjective, socially and culturally embedded): This activity focuses on constructing scientific knowledge which can be influenced by scientists’ previous knowledge, training, and experiences.
The method for this activity is that students are divided into small groups and shown several different pictures with portraits of both an old lady and a young lady portraits embedded in each picture.
Pre-service science teachers are asked to tell what they see in each picture.
3. Elephant’s Legs (science as theory-laden and subjective, socially and culturally embedded): This activity focuses on constructing scientific knowledge that is affected by scientists’ previous knowledge, training, and experiences as well. The method for this activity is the same as described in the “Young? Old? Activity”. A Lipton tea bag label (Figure 5) was used in this activity. Students were amused to realize that they could find different materials from their daily life to teach some aspects of the NOS.
Figure 5.
4. The Puzzle activity (tentative scientific knowledge): This activity stresses that scientific knowledge is subject to change with new observations and with the reinterpretations of existing observations. The method for this activity is same as in previous sections.
A small group and then a whole-class discussion was conducted for each activity that aimed to explicitly highlight the aspects of the NOS and involve students in active discourse regarding their ideas on some aspects of the NOS. In these discussions, I encouraged students to make links between the activities applied and scientists’ real life experiences toward developing scientific knowledge. Subsequent discussions focused on the distinction between observations and inferences, the tentative nature of scientific knowledge, theoretical constructs in science, the role of creativity, imagination, and background knowledge, and the impact of the social and cultural factors in devising scientific explanations. This non-context based NOS instruction was intended to provide the pre-service science teachers with a NOS framework by introducing and sensitizing them to these aspects of the NOS.
Theoretical framework for the study: Phenomenography
Since this study was concerned with pre-service science teachers’ views and understanding of the NOS, the design of this qualitative study was viewed within a phenomenographic framework.
Phenomenography is the study of the different ways in which people experience the world. In other words, its aim is to discover the range of ways people in a group experience, conceptualize, notice, and understand various aspects of phenomena in the world around them (Bowden et al., 1992). In phenomenographic research, the researcher chooses to study how people experience a given phenomenon (Ornek, 2008). A phenomenographic framework was used to ascertain how the pre-service science teachers understand the aspects of the NOS.
Data were collected from multiple sources:
- Using the VNOS-C, the Views of Nature of Science version C (Abd-El-Khalick, Bell, & Lederman, 1998; Lederman, Schwartz, Abd-El-Khalick, & Bell, 2001).
- The Myths of Science survey (McComas, 1998) explores widely-held, yet incorrect ideas about the aspects of the nature of science.
- Associated semi-structured interviews: to track the changes in the NOS views of pre-service science teachers by using the VNOS-D, The Views of Nature of Science version D (Lederman & Khisfe, 2002) at the end of the course.
- A workshop was conducted about the NOS in the Spring 2009 to follow up pre-service science teachers’ progress vis-à-vis understanding of the aspects of the NOS and video-recorded.
The questionnaires, the VNOS-C, and the Myths of Science were all designed to elucidate participants’ views regarding the components of the NOS and underlying their views. In addition, the VNOS-D survey was used for semi-structured interviews to elucidate pre-service science teachers’ own views with regard to aspects of the NOS. Open-ended survey items including interview questions allow the pre-service science teachers to reveal their own opinions regarding the aspects of the NOS and the reasons that underlie their views (Lederman, 1992; Lederman & O’malley, 1990). The ten-item open-ended survey (VNOS-C), the 15-item open-ended survey(Myth of Science), and the seven-item open-ended survey (VNOS-D) used in this study were previously applied and validated by Abd-El-Khalick (1998) and Lederman et al. (2001), McComas (1998), and (Lederman & Khisfe, 2002).
The main research question that guided this study were “What were pre-service science teachers’ views of the NOS? and What was the influence of the explicit constructivist-inquiry oriented approach on pre-service science teachers’ views of the NOS?”. Qualitative design was used to answer the research questions. The study data were collected in Fall 2008 and Spring 2009, using an open-ended survey, The Views of the Nature of Science Form C (VNOS-C) was used to assess participants’ views of the NOS before and after the Science Method course, Teaching and Learning Science 1. This survey consists of ten open-ended items that assessed participants’ views of the tentative, creative, empirical, and subjective nature of science; social and cultural embeddedness in science; observation and inferences; and theories and laws. In addition to the VNOS-C, the Myth of Science Survey was used to investigate participants’ views of the NOS prior to and at the end of the course. This survey consists of 15 open-ended items that probe participants’ views of the same issues as the VNOS-C does. The author implemented the teaching activities, and then conducted semi-structured interviews with all pre-service science teachers at the end of the course using the VNOS-D survey. This survey consists of the seven open-ended items that investigates participants’ views of the NOS with regard to the aforementioned aspects of the NOS. Interviews aimed to investigate participants’ views of the NOS in depth. Interview findings were also used to examine the validity of pre-service science teachers’ post-test responses to the survey items because what they had written might not have reflected what they explained in the interviews.
During the Fall 2008 semester, pre-service science teachers’ understanding of the NOS was examined through the use of the VNOS-C and the Myths of Science survey. 25 pre-service science teachers completed the surveys as a pre-test and post-test. After the first semester, 6 of them took part in semi-structured interviews in which the VNOS-D was used to elicit more detailed responses in relation to pre-service science teachers’ responses on the questionnaires. All interviews were audio-taped and transcribed for analysis.
Two types of triangulation were used to establish credibility of the results of survey, interview, and video records data. One was to involve another investigator’s interpretation of the data obtained from both surveys and independent interviews (Patton, 2002). We compared the findings and found that our results were compatible. This approach was carried out because the researcher was also the instructor of the course. Otherwise, it would not be possible to avoid the researcher’s bias. The second method of triangulation was to include the primary data in the results. The inclusion of excerpts from the interviews allows the reader to see exactly the basis upon which the conclusions were made.
Data obtained from the surveys, corresponding interview transcripts of all pre-service science teachers, and transcripts of the video records, were all analyzed using inductive analysis with the assistance of a data-management software program called ATLAS-Ti. Major coding categories derived from the data were formed to make sense of pre-service science teachers’ responses and to describe the variety of their responses. I created the coding categories for an initial coding scheme for data from surveys, interviews, and video records. After that, the other researcher was involved in coding to establish consistency of the analysis. Another researcher and I computed the reliability of the data by comparing coding decisions using the inter-coder reliability formula: Reliability= [number of agreements / (total number of agreements + disagreements)] (Miles & Huberman, 1994, p.64).
According to the results of the calculations, the inter-coder reliability levels for pre-and post-tests, interviews, and video analysis were 0.75, 0.84, 0.92, and 0.90 respectively. We reexamined the contradictory evidence in the data and decided to do some further refinement of coding categories. As a result, we found our results were compatible after some modification of coding categories.
The categories were tentativeness; empirical basis; subjectivity; creativity/imagination; social/cultural embeddedness; observations/inferences; theories/laws. The same procedure was done by the other researcher to confirm reliability in the data and we found our results were compatible. Moreover, the data obtained from the NOS surveys were generated into pre-instruction and post-instruction profiles of pre-service science teachers’ views of the NOS in the course. Some quotes were used to support the assertions made and enrich discussions.
