Teaching is a complex, dynamic, ill-structured process. In this process, known and valued information is newly built, jointly rebuilt, and passed from one source to another. There are multiple approaches to teaching and learning, each emphasizing different aspects of the process and each according the participantsā different roles. These approaches stretch along a continuum of who (the teacher, text, or learner) has which type of responsibility for which aspects of presentation and acquisition of knowledge. Conceptions of the learner vary from that of the rediscoverer and reinventor of human knowledge (Papert, 1980), to an apprentice in a socially situated system (Brown, Collins, & Duguid, 1989; Scribner, 1984a, 1984b), to an acquirer of well-designed stacks of information (GagnĆ© & Brown, 1961). Related conceptions of the role of the teacher in teaching also vary from seeing the teacher as a relatively passive responder, to collaborator or facilitator (with the teacher as a problem poser and arranger of conditions for learning), to one that is primarily didactically directive. The fundamental nature of the teacherās task and the knowledge base that he or she must have differ depending on how the role and activity are conceptualized. Arguments in support of a particular position are traditionally bolstered by a rich psychological conceptualization of learning. Comparably rich psychological explorations of teaching are somewhat rarer.1 Almost never are the two studied in tandem. Although the systematic study of teaching has a long and rich tradition, considering the teacher as a complex, rational planner and organizer and presenting data to support that view is, by comparison, a newer enterprise (Shavelson & Stern, 1981; Yinger, 1980; Yinger & Dillard, 1987).
In the remainder of this section, three approaches to teaching are contrasted: (a) discovery, (b) facilitator, and (c) didactic director. Within the facilitator model, a distinction is made between task-centered learning that is anchored by life tasks and task-centered learning that is anchored by disciplinary tasks. The section concludes with a discussion of the stance towards teaching that is taken throughout the chapter, namely, that it is a complex web. Strands in the web help the teacher develop coherence for the complexity, dynamism, and ill-structured nature of the activity.
Discovery. The discovery model of teaching is fundamentally a discovery model of learning, where teaching is seen as the construction of a situation in which the learner has all the tools necessary for discovery; the learnerās personal interest both motivates and structures the task of learning (Dewey, 1963; Montessori, 1965; Neill, 1960; Piaget, 1954). The student selects the topics of inquiry, determines the path for finding out about the topic, and decides the end point. Unless a student knows to ask for them, the fundamental structure and epistemology of a discipline remain masked. A student has to discover, for example, that keeping notebooks and records of inquiry in some systematically but neutrally retrievable way is helpful in building up knowledge of more than one episode and in discovering patterns (Siegler & Liebert, 1975). The psychological support for the learner in this role is twofold: First, he or she builds new knowledge from existing intuitions and schemata and so remembers the new knowledge; second, the learner selects topics of inherent interest and value and works from his or her own motivations. The psychological criticism for this approach is pragmatic: First, the student may never discover the ārightā thing (Ausubel & Schiff, 1954; Joshua & Dupin, 1987); second, the student does not have an opportunity to use conventional language and formations that aid recall of a correct piece of knowledge and link it to shared knowledge in a wider community (Leinhardt & Ohlsson, 1990). Under a strict view of discovery, teaching is considered good in those cases in which it facilitates but does not interfere with the studentās complete construction of the self-selected knowledge. The teacher is seen as librarian who serves as a repository of information that the student can tap. In a discovery model, the teacher must be astute about the studentās psychological development and capacity for insightful observation, as well as about the global pattern of a discipline.
Facilitator. The models in which the teacher is the arranger or collaborative facilitator have been well articulated by Montessori (1965) and Dewey (1963). In these collaborative models, the student constructs knowledge systematically under guided social conditions. Errors are corrected through public and private inspection of results and effects (Brown & Palincsar, 1984; Lampert, 1986). In these models, teachers watch and anticipate the thinking and reasoning of a child. They observe carefully how a particular pedagogical device is interpreted. Teachers pose questions and offer problems; they facilitate searches of knowledge repositories such as libraries or museums; they encourage natural experiments; they focus studentsā attention on particular portions of the enterprise. They are guides and planners. To be effective within the discipline, they must have deep disciplinary knowledge. To be effective as teachers, they must have deep pedagogical knowledge. This tradition has two identifiable approaches, each treating the role of the teacher similarly but requiring different knowledge bases.
One approach assumes knowledge is most naturally acquired around tasks and projects. This tradition has its latest manifestation in the theories of activity-based learning proposed by such followers of Vygotsky (1978) as Brown and Reeve (1987); Bereiter and Scardamalia (1989); and Scardamalia, Bereiter, and Steinbach (1984). The context of learning in these theories is a relatively natural, āauthentic life taskā or project. In this setting, the teacher helps students to draw out the subject-matter knowledge content from tasks. For example, a class plans an investigation or writes a book about a specific topic. Roles are decided upon. Disciplinary knowledge is gained from multiple sources and pooled: in math, from planning the costs and estimating and projecting rates of change and growth; in science, from structuring the task and charting results; in writing, from writing about different aspects of the enterprise (Bereiter & Scardamalia, 1989; Brown, 1992; Scardamalia et al., 1984). The knowledge is acquired in a situation that itself carries both the problem and the solution (Carraher, Carraher, & Schliemann, 1985; Schliemann & Acioly, 1989). The teacherās task is to orchestrate, manage, and respond supportively.
In a second approach to the facilitation conception of teaching, the focus is less on project-based contextualization of problems than on the disciplineās own task space (see Nesher, 1992; White, in press). One example of this more abstract approach is Montessoriās didac...