context of learning" (NRC, 2000, p. 35). In developing a suitable model for investigation
"the aim must therefore be to develop a general model of 'investigational work' which learners can use and apply in a number of different situations" (Wellington, 2000, p. 162).
The need is for a flexible model that provides guidance for learners and teachers who are comfortable with more autonomy and open-endedness. as well as for learners and teachers who have little previous inquiry experience and need more guidance (Songer, Lee &
McDonald, 2003). One of the foci of the current study was to develop such a model which could assist teachers in the implementation of scientific investigations as described in the RNCS (Department of Education, 2002b) in South Africa.
Learning through inquiry transcends learning which is directed wholly by the teacher or textbook; the autonomous inquirer assimilates his experience more independently. He is free to pursue knowledge and understanding in accordance with his cognitive need and his individual level and rate of assimilation. (p. 74)
In doing an investigation, learners learn not only concepts and principles, but self-direction and responsibility. In teacher-centred instruction, on the other hand, "much of the
opportunities for developing these talents are denied to the student by the instructor. The instructor provides the self-direction and retains the responsibility, etc." (Sund &
Trowbridge, 1973, p. 65). However, as Faraj (1986) suggests, when doing investigations
"the learner is seen as a 'programmer' of his own learning, and he is the centre of the learning experience" (p. 40). In such a learning situation, the learner should be free to initiate the investigation by posing a question, then can generate his own theories, test them through experiments and through gathering suitable data, and finally formulate a
conclusion (Faraj, 1986). In doing investigations, learners play an active rather than a passive role. This active learner involvement in a task is highlighted by Bibens (1 980) who states that:
Inquiry requires that students participate actively, and interact directly, with the content.
The learner is not allowed to sit passively while the instructor reviews the main thrtist of the learning experience for him. In essence, inquiry strongly suggests that the learner is his own teacher. (p. 90)
Investigative inquiries therefore provide opportunities for a shift from a teacher-centred to a learner-centred curriculum where learners have much autonomy and control over their learning.
The principles of constructivism lay the foundation for understanding the need for learner autonomy in scientific investigations. In the constructivist view of learning, the learners are actively involved in their learning as they set their own goals and control their own decisions (Driver & Bell, 1985). The knowledge which the learner gains is constructed within his cognitive structure, and depends on his experiences in the learning environment (Grabinger & Dunlap, 1995). According to Fosnot (1996), in this setting "the traditional hierarchy of the teacher as the autocratic knower and learner as the unknowing, controlled subject studying to learn what the teacher knows begins to dissipate as teachers assume more of a facilitator's role and learners take on more ownership of the ideas" (p. iv). The principles of constructivism therefore reinforce the desirability of learner autonomy which is a characteristic of learners doing scientific investigations.
Also, in contrast to traditional classrooms, teachers who hold a constructivist view of learning know that learners bring with them to the classroom a diverse set of alternative conceptions that they have developed to explain the world around them (Driver, 1983).
These teachers realize that prior conceptions brought to class are often based on
misinformation or naïve understandings of complex subjects. These preconceptions are generally ideas that are reasonable and appropriate in a limited context, but learners inappropriately apply them to situations where they do not work (Anderson & Smith,
1987). Learners often hold tenaciously to these ideas, and their preconceptions can be resistant to change, particularly using conventional teaching strategies (Wandersee, Mintzes & Novak, 1994). in traditional classrooms, such misconceptions often go
undetected. Uncovering these misconceptions or naïve conceptions forms the foundation of a constructivist lesson. In order for learners to give up their previous alternative
conceptions about a particular topic, they have to experience something that challenges their misconception and allows them the opportunity to form new beliefs. According to Piaget (as cited in Llewellyn, 2002), for conceptual change to occur, the child must be faced with new conceptions that are inconsistent with presently held beliefs. Piaget called this cognitive conflict. Hewson and Lemberger (2000) explain that learners change their ideas when they find these ideas to be unsatisfactory, that is when their present ideas do not sufficiently describe or explain an event or observation. The learner must be convinced that the scientific explanation is better than theirs. Learners only change their ideas when they discover alternatives that seem plausible and appear to be more useful.
The investigative approach which stresses learner autonomy is a viable teaching strategy to test the degree of fit between one's preconceptions and the scientific explanation of things.
During the investigation, the learner makes a prediction based on his or her present understanding, and then gathers evidence to test this understanding. At times, the learner goes on to record observations and measurements that point out a discrepancy or difference between the predicted and the observable results. This can cause disequilibrium, forcing the individual make accommodations with his or her present cognitive structures to allow the new knowledge to replace the previous (Llewellyn, 2002).
The new emphasis in science education reform in South Africa and other countries is on learner autonomy and scientific investigations. It has been shown in the argument so far
that these concepts are inextricably related. The full benefit of scientific investigations can only be realised if learners are actively doing these investigations themselves.
2.6 A THEORETICAL FRAMEWORK FOR TEACHER SUPPORT OF