Magnetic Force
...uli is processed (ROM in the case of the computer, in which is stored its operating system or other processing software), have a long term memory (hard disk and floppy disk), and are capable of generating responses. IPC is regarded by McInerney et al. (2002) as “probably the leading conceptual framework for the study of cognitive development and learning.” (p.74) The hallmark of IPC in teaching and learning is the use of a concept (or concepts) to process data and construct understanding. Scenario 3 has Roberto introducing students to the concept that a compass will oscillate many times before orienting itself within a strong magnetic field. Students in this scenario are given input data showing the number of times a compass oscillates within a given geographical location which they are to use to create an observable response in the form of a graph. Roberto hopes that his students will process information in the following manner: 1. Notice that a town’s compass oscillates many times before it settles on a stable direction. 2. Process this information using the given concept to construct an understanding that the town lies in a strong magnetic field. 3. Group towns of similar magnetic field strength according to their proximity to the earth’s poles. 4. Observe that the towns with strong magnetic fields are close to the earth’s poles. 5. Process this information to construct the concept of strong magnetic field strength at the earth’s poles. The system used by Roberto to introduce his class to the concept that ‘when a compass is placed in a strong magnetic field, it oscillates many times before it settles on a stable direction’ is consistent with Ausubel's Reception-Learning Model. “In reception learning the material to be learnt is presented to learners in a relatively complete and organised form.” (McInerney et al, 2002, p.110). Ausubel advocates the use of an ‘advance organiser’ in his Reception-Learning Model. An advance organiser is an explanation that precedes the introduction of a new topic (in this scenario compass oscillation) that provides structure to the new topic by relating it to what students already know. An ‘expository organiser’ is a type of advance organiser that exposes students to a concept. An example of an ‘expository organiser’ is the magnet and iron filing experiment, by which Roberto hopes to prepare his students for the concept of compass oscillation in magnetic fields. Roberto’s explanation of how a compass oscillates in a magnetic field is consistent with Ausubel’s theory that concepts must first be presented to learners before learning can take place. In receiving the concept, it is hoped that students will be able to extend and develop the application of the concept when presented with new information, such as geographical data and the number of compass oscillations. The explanation is the framework within which students are expected to process new information. If well implemented, IPC in conjunction with the Ausubel Reception-Learning Model can be an effective teaching and learning technique. Its positive aspects include the transfer of knowledge across contexts, and the retention of meaningful information. An example from outside this scenario would be the ability of a musician to play different musical instruments within the same instrument family. For example, each instrument of the string family uses the same concept of drawing a bow across strings or plucking strings with one’s fingers. In this case, the concepts of plucking and bowing diminish the need for learning new concepts, that is, of learning to play each instrument ‘from scratch’. Roberto hopes that the knowledge of compass oscillation can be transferred by the students to the data presented. Meaningful information exposed by a teacher can help students to connect knowledge to new topics. In the case of the magnet, paper, and iron filings expository organiser, students can use the meaningful ‘tactile’ information of magnetic strength near poles (established by blowing the iron filings gently) to form connections with the new topic of compass oscillations in the earth’s magnetic field. Unfortunately, in the construction of deep understanding of abstract ideas, IPC and Ausubel’s Reception-Learning Model also exhibit significant teaching and learning disadvantages in the form of the imposition and ownership of concepts by the teacher, the limiting of students to one concept, the creation of the perception that a concept is the objective truth, the misunderstanding of the tasks, students learning something that wasn’t intended, and even the meaninglessness of information given devoid of context. Through his imposition and exposition of the concept to his students, Roberto has announced himself as a transmitter of knowledge and students are not encouraged to devise their own concepts to fit the data. Consequently, students tend not to develop ownership of the concepts presented to them, and their retention of concepts is diminished. Students are often starved of opportunities in which to construct knowledge when given a concept at the commencement of their learning. Consequently, students tend not to think beyond the boundaries of the imposed concept. Roberto’s formulation of the concept as an objective truth entails that it is something which the students should accept. The authoritarian presentation of concepts removes the ability of students to examine, challenge, and accept or reject evidence. In the same way that astronomers once worked within the framework of an earth-centric universe, so Roberto’s students must work within the framework of strong magnetic poles causing many oscillations of a compass. In this scenario, students might think that the purpose of their learning is the construction of a graph, rather than seeking to understand the nature of the earth’s magnetic field. The construction of the graph does not call on students to use the concept introduced by the teacher, but rather relies upon the students’ procedural knowledge of plotting variables on horizontal and vertical axes. The concept has little meaning to the students, because it has only tenuous links with what they already know. When the concept is introduced, they have not yet seen a compass in the classroom, let alone watched it oscillate. Roberto hopes that the concept of magnetism alone, demonstrated by the expository organiser, will provide sufficient background knowledge from which students can extrapolate answers to questions about the behaviour of compasses in the earth’s magnetic field. Roberto, as the transmitter of knowledge, can readily see the connections between the two contexts, but the students might not. This is witnessed by Roberto’s uncertainty that the ‘strugglers’ in his class might not have understood the concept at the end of the two lessons. All of these problems lead towards low student motivation and participation and are compounded when the repository of all knowledge is no longer prepared to spend more time on the topic. Janette’s technique is more successful in helping students to construct deep understanding of an abstract idea. This is exhibited by two ‘strugglers’ in her class who demonstrate an understanding of the concept through their explanation. Janette’s teaching method is the opposite of Roberto’s in that, rather than telling students the concept to be acquired and requiring them to process information through it, students are encouraged to first discover information, and explore it within a social context from which concepts can be derived. The placement of the information in a social context helps to generate more information which students can examine and draw conclusions from in the development of a concept that best fits the available data. The techniques that Janette uses are based on Social Constructivism combined with Bruner’s Discovery-Learning Model. Social Constructivism “focuses on the construction of shared knowledge in social contexts” (McInerney et al., 2002. p4.). In Social Constructivism, knowledge is viewed as a resource belonging to society. New learners are socialised with this knowledge and in so doing, gain and share that knowledge with others in the society. Learners contribute to the growth of knowledge and increase the volume of knowledge through their interaction with it. Social Constructivism proposes that “learning is a process through which we become one with the societal collective through carrying out personal activity in collaboration with other people” (Davydov, 1995 in McInerney et al. 2002, p.45). Science educators must go to great lengths to ensure that their students understand scientific concepts within a social, rather than a personal context. If a personal construction of scientific concepts is allowed, then “anything is allowed to count as science if it constitutes ‘understanding of the world’ in terms meaningful to the learner and is based on arguments convincing to the learner” (Hodson & Hodson, 1998, p.34). Hence, particularly in the sphere of scientific knowledge, Social Constructivism suggests there is an objectivity of societal knowledge. Vygotsky, the father of modern social constructivist psychology, sought to understand the role language played in the development of higher cognitive functions. “Children solve practical tasks with the help of speech, as well as their eyes and hands” (Vygotsky, 1978 in Hodson et al., 1998, p.36). This differs from personal constructivist approaches including IPC in that concepts are “co-constructed through social interaction” (Hodson et al., 1998, p 37), rather than personally and internally. The process by which individuals accept concepts, Vygotsky calls internalisation. Vygotsky also proposed the concept of a Zone of Proximal Development. The Zone of Proximal Development is: the distance between the actual development level as determined by independent problem solving and the level of potential development as determined through problem solving under adult guidance or in collaboration with more capable peers. (Vygotsky, 1978 in Hodson et al., 1998, p.36) Vygotsky believed that learning was not effective unless it was aimed at the Zone of Proximal Development. “It is the loan of the [adult’s] consciousness that gets the child though the Zone of Proximal Development” (Bruner, 1986, in Fosnot, 1996, p. 21), and it is within this zone that Scaffolding plays an important role. Scaffolding in constructivist learning is similar to the way in which Scaffolding is used in the construction of a building, before gradually being removed to allow the building to stand freely. Scaffolding in a teaching and learning context is best represented by the information that the teacher directs the students through. This is important in scenario three, because students are highly unlikely to discover the nature of the earth’s magnetic field without the provision of Scaffolding. The hallmark of Social Constructivism in teaching and learning is the sociocultural participation of students and learners. Social interaction between teacher and learner is required to help mediate learning, and Scaffolded instruction is required to extend students beyond their current capacity. Janette used the experiment of the magnet and iron filings to establish common classroom knowledge (socialisation). She then facilitated the students’ discovery of the oscillation of compasses (Scaffolding) upon which she hoped students would construct the concept of the earth’s magnetic poles. This information was shared with students on a global level, who in turn shared their discovered information to create a global Scaffold. Using language, students discussed the ways in which the phenomena observed could be explained to arrive at socially construced concept. The system by...