Conclusions and Implications

As a result of the data analyses, we have constructed two types of teacher knowledge about models and modelling in the context of teaching PUSc.: Type A and Type B. With regard to thecontent of both types of teacher knowledge, we conclude that within each separate domain of the teacher knowledge investigated a combination of different perspectives was shown. An example is the combination of a behaviourist and a cognitive view in the domain of general pedagogical knowledge. This combination can be explained by the supposition that the teachers’ current pedagogical knowledge is shaped by the educational principles of the leading theories in learning psychology in the last decades, and the idea that teachers usually develop their knowledge gradually, in a process of picking up theories (implicitly) applied in activities and techniques in schoolbooks and other materials, professional training, and so on (see section 2.3.1). In our view, new knowledge does not just replace old ideas. Since teachers’ preferred way of learning is “evolutionary and fundamentally conservative, not revolutionary and transformative” (Thompson & Zeuli, 1999, p.350), teachers’ knowledge is likely to change slowly and bit by bit, while possibly representing different perspectives (“rival hypotheses”; Kelly, 1955) at the same time. From this view on knowledge development, we can understand the appearance of a

constructivist perspective on learning and teaching (Greeno et al., 1996), while the newer, situative perspective (as defined by Greeno et al., 1996) was still missing in the teachers’ interview responses. The latter perspective can be found in schoolbooks (in debating activities, for instance), but was not recognized by the teachers, as such. Because teachers usually pick up activities (Wallace, 2003) that seem to fit with their own styles, settings and students, they apply these activities from their own perspective, for example, a constructivist one. Our view on teacher knowledge development can also explain that most of the teachers showed a combination of two perspectives on scientific models and modelling: this may be the result of combining a traditional positivist view on science, related to their prior disciplinary education (cf. Van Driel & Verloop, 1999), with a way of thinking that they picked up from recent innovations in science education.

With regard to thestructure of the teachers’ knowledge, we conclude that in both Type A and Type B of teacher knowledge, PCK was found to be consistent with general pedagogical knowledge. In Type A, in particular the PCK of instructional strategies was found to be well developed. Teachers who represented Type A of teacher knowledge had developed PCK about ‘Models of the Solar System’ in which the model content of ‘Solar system and Universe’ (Program Domain F) was emphasized. In Type A, PCK of instructional strategies, PCK of students’ understanding, and PCK of ways to assess students, all reflect a focus on model content. Type B was more extended and more integrated in terms of PCK. Teachers who represented this type of teacher knowledge had developed PCK about ‘Models of the Solar System’ in which the various program domains of the new science syllabus PUSc. were more connected. PCK about instructional strategies, PCK about students’ understanding, and PCK about ways to assess students, all reflect a view in which model content (Program Domain F) is combined with model production (Domain A) and model thinking (Domain B). See Table 2.10. In both Type A and Type B of teacher knowledge, subject matter knowledge was least explicit, and not directly related to the other knowledge domains (i.e., general pedagogical knowledge and pedagogical content knowledge).

Table 2.10 Structure of Teacher Knowledge Type A and Type B

Main perspective in the general pedagogical knowledge

Most developed element(s) of the pedagogical content knowledge of ‘Models of the Solar System’

Main focus in the pedagogical content knowledge of ‘Models of the Solar System’

Type A Behaviourist /

cognitive

PCK-instructional strategies Model content

Type B Cognitive /

constructivist

PCK-instructional strategies, PCK-students’ understanding, PCK-ways to assess students

Model content, Model production, and Model thinking

On the basis of the results of this study, we conclude that those teachers who are representing Type B of teacher knowledge about teaching models and modelling in

PUSc., may have realized more aims of the educational innovations in secondary education in the Netherlands, than those representing Type A. First, the teachers representing Type B seem to have adopted pedagogical approaches which aimed to stimulate self-regulated learning and to decrease the emphasis on teacher-directed education, based on cognitivist / constructivist perspectives on learning and teaching. Second, in teaching models and modelling, these teachers seem to have connected, more or less, the educational aims of various program domains (i.e., Domains A, B, and F) of the new syllabus on Public Understanding of Science (PUSc.). In contrast, those teachers who are representing Type A of teacher knowledge seem to have adopted mainly teacher directed teaching approaches, based on behaviourist / cognitivist perspectives on learning and teaching and primarily aimed at the transmission of model content, that is, content of models of the solar system (Program Domain F).

Because of new experiences teacher knowledge will change (gradually), over the years. So, it is possible that teacher knowledge Type A will develop in the direction of Type B when teachers become more experienced in teaching PUSc. We assume that teacher knowledge development is a process of picking up new materials, strategies and, implicitly, pedagogical and epistemological perspectives. Therefore, to improve a successful implementation of the aims of the above-mentioned innovations, we recommend (among other things) to apply additional high quality teaching materials in which those aims are realized in a transparent and attractive way.

On the basis of the results of this study, it is not possible to make a generalization to the whole population of teachers of PUSc., because our respondents only represented a small part of the teachers, that is, those who used teaching method ANtWoord. A large-scale follow up study is necessary to investigate whether the above-mentioned knowledge Types A and B can be found in the whole of the population of teachers of PUSc. Given the small sample in the present study, it is possible, obviously, that additional Types will be found, or that, alternatively, a hybrid Type consisting of a blending of Types A and B, can be identified.