【正文】 ty course work in which I was involved.The Research FocusAs I identified these themes, I reflected upon my own classroom practices. Although some curriculum reform measures (as the use of alternative assessment techniques) were evident, Ifound that generally, my practices represented traditional instructional techniques rather thaninnovative ones. In my reading on reform measures, however, I encountered the process ofinquirybased learning, which greatly intrigued me. After further study, I became convinced thatinquirybased learning was the vehicle that would allow me to integrate curricular reforms into my classroom and help me move away from the more traditional style of teaching toward a moreconstructivist approach. I decided to adopt an inquirybased orientation (or problembasedlearning as I later came to call it) in my teaching of science.Once problembased learning was chosen as the vehicle for this curricular reform, I wishedto investigate its effectiveness in transforming my classroom practices. So, my original researchquestion was: Can problembased learning be used to transform classroom practices and thusinstitute a more constructivist approach to learning? As I began to conduct my research, however,the emergent design of the study led me to incorporate particular fields of interest into thisresearch question. These fields of interest reflected the themes that I had identified within thecurrent curriculum reform efforts in the science education literature. In this manner, my researchquestion for this study became:Can I, as an instructor, teach science in such a way that: the use of science in real life is ernphasised。 an interdisciplinary approach is utilised。 assessment is an integral part of instruction。 and learning is studentdriven, not teacherdirected?Overview of the StudyFor this study of the implementation of problembased learning, I chose two biochemistryclasses taught within a Health Occupations Academy at a Florida secondary school. Within theseclasses, over the course of one school year, high school juniors and seniors encountered sevendifferent problems. The topics ranged from mosquito infestations to poisoning mysteries. No matter the topic or the length, however, students worked in groups to solve each I provided the setting for each problem and set deadlines, student groups wrote problem statements and planned their own research agenda. Before presenting problems to students, I wrotea curriculum alignment guide for each problem, using the Florida Department of EducationSunshine State Standards. These standards, then, defined the intended curriculum to be coveredby students working on the problem. Alternative means were used to evaluate student performanceon the problems and included self, peer, and teacher assessments.MethodologyThe investigation of problembased learning in my secondary biochemistry classes wasconducted during the 199697 school year. The research was qualitative in nature and stressed thesocially constructed nature of reality, the intimate relationship between the researcher and whatis studied, and the situational constraints that shape inquiry (Denzin amp。 Lincoln, 1994, p. 4).In this classroom39。s socially constructed reality, interactions took place between students and between students and myself. Qualitative methods for capturing interactions utilise the human instnunent, included talking to people, observing their activities, reading their documents,assessing the unobtrusive signs they leave behind, responding to their nonverbal cues, and the like (Guba amp。 Lincoln, 1989, p. 176). The students in this study constituted the people, or stakeholders. So, the students generated some of the data and as a teacherresearcher, I collected anecdotal records and piled contextual evidence in order to preserve the interplay of classroom interactions, events, and exchanges. Such record keeping ensured that the rich descriptions of the classroom environment needed in order to serve as the basis for conclusions were secured (Denzinamp。 Lincoln, 1994).Guba and Lincoln (1989, p. 50) want to bring to light the claims, concerns, and issues of the stakeholders involved in the investigation. In order to uncover such claims, concerns, and issues, Guba and Lincoln (1994, p. 111) remend a hermeneutic, dialectic process in which individual constructions are drawn fi39。om interactions between and among [the emphasis is theirs] investigator and respondents. In such a hermeneutic/dialectic process, stakeholders are identified and then interviewed, surveyed, sampled for opinions, asked to respond, and so on. An important characteristic of the hermeneutic process is that data collection and data analysis are data are collected, they are immediately analysed and then used to direct new data collection efforts. This process continues until all stakeholders reach a joint construction, based upon their responses in the hermeneutic process. Guba and Lincoln (1989, p. 180) term these cycles of stakeholder input as multiple iterations. Following such a process will, according to Guba and Lincoln (1989), resuk in an emergent design for the research. In support of this emergent design,Denzin and Lincoln (1994, p. 2) describe the researcher as a bricoleur, who is a Jack of all trades or a kind of professional doityourself person。 whose choice of tools to use, which research practices to employ, is not set in advance.The bricoleur39。s product is a bricolage, a plex, dense, reflexive, collagelike creation that represents the researcher39。s images, understandings, and interpretations of the world or phenomenon under analysis (Denzin amp。 Lincoln, 1994, p. 3). Guba and Lincoln (1989, p. 223)suggest that the most useful format for the bricolage is the case study, as this format allows readers to see how the constructors make sense of it [the joint construction], and why. In this manner,the case study helps readers understand the joint const