Learning Material for Concept and Conceptual Change

7/27/2019 Learning Material for Concept and Conceptual Change

1/28

1

Learning Material for concept and conceptual change

Introduction

The concept of concepts is difficult to define, but no one doubts that concepts are fundamental tomental life and human communication. Cognitive scientists generally agree that a concept is a

mental representation that picks out a set of entities, or a category. That is, concepts refer, and

what they refer to are categories. It is also commonly assumed that category membership is not

arbitrary but rather a principled matter. What goes into a category belongs there by virtue of

some law-like regularities. But beyond these sparse facts, the concept CONCEPT is up for grabs.

As an example, suppose you have the concept TRIANGLE represented as a closed geometric

form having three sides. In this case, the concept is a definition. But it is unclear what else

might be in your triangle concept. Does it include the fact that geometry books discuss them

(though some dont) or that they have 180 degrees (though in hyperbolic geometry none do)? It

is also unclear how many concepts have definitions or what substitutes for definitions in ones

those dont.

In metaphysics, and especially ontology, a concept is a fundamental category of existence.

In contemporary philosophy, there are at least three prevailing ways to understand what a

concept is:

Concepts as mental representations, where concepts are entities that exist in the brain. Concepts as abilities, where concepts are abilities peculiar to cognitive agents. Concepts as abstract objects, where objects are the constituents of propositions that

mediate between thought, language, and referents.

Eggen and Kauchak (2004) defined concepts as ideas, objects, or events that help us understand

the world around us.

Functions of concepts

For purposes of this review, we will collapse the many ways people can use concepts into two

broad functions: categorization and communication. The conceptual function that most research

has targeted is categorization, the process by which mental representations (concepts) determinewhether or not some entity is a member of a category. Categorization enables a wide variety of

subordinate functions because classifying something as a category member allows people to

bring their knowledge of the category to bear on the new instance. Once people categorize some

novel entity, for example, they can use relevant knowledge forunderstandingandprediction.

Recognizing a cylindrical object as a flashlight allows you to understand its parts, trace its

functions, and predict its behavior. For example, you can confidently infer that the flashlight will


2/28

2

have one or more batteries, will have some sort of switch, and will normally produce a beam of

light when the switch is pressed. Not only do people categorize in order to understand new

entities, they also use the new entities to modify and update their concepts. In other words,

categorization supports learning.

Concepts are also centrally involved in communication. Many of our concepts correspond tolexical entries, such as the English word flashlight. In order for people to avoid

misunderstanding each other, they must have comparable concepts in mind. If As concept of

cell phone corresponds with Bs concept of flashlight, it wont go well if A asks B to make a

call. An important part of the function of concepts in communication is their ability to combine

in order to create an unlimited number of new concepts.

These functions and associated subfunctions are important to bear in mind because studying any

one in isolation can lead to misleading conclusions about conceptual structure.

Childrens Learning ofConcepts and Names

Perhaps the most dramatic example of concept learning is the performance of young children,

who can learn up to 15,000 new words for things by age six (Carey, 1978). Of course, learning a

new word and learning a new concept are not the same, but they are closely related (Clark,

1983). For example, a childs knowing the word dog and having the concept of dog are two

different achievements. Knowing a concept might precede learning its name or alternately,

hearing a name for an object might lead to further investigation of the concept (e.g., Waxman,

Shipley, & Shepperson, 1991). Early concept learning by children appears to be guided by rather

general principles or knowledge structures. Given the large number of concepts learned by

children and the systematic biases that are apparent in this learning, it is plausible that thechildren are being influenced by general knowledge rather than by specific knowledge about

other categories. Markman (1989, 1990) suggested, and reviewed evidence for, certain

constraints that would guide category learning by children. First, according to the whole object

assumption, a novel category label is more likely to refer to a whole object than to its parts. Upon

hearing a category label such as dog for the first time, a child would assume that this label

refers to a dog rather than to some part of a dog such as its wagging tail. Second, according to the

taxonomic assumption, learners will tend to use new words as taxonomic category labels rather

than as ways to group things by other relations. For example, after a child has learned about his

or her first dog, the child would extend this label to other animals that appear to be in the same

taxonomic categoryother dogs--rather than extending the label to objects that are otherwise

associated with the dog. That is, the child would not call the dogs leash a dog, or call the

dogs owner a dog. Third, the mutual exclusivity assumption would provide further guidance

in early category learning. In following this assumption, a child would favor associating

particular objects with just one category label. Thus, when learning a new category label, the

child would look for some object for which he or she does not already know a label. For

example, say that a child already knows the word dog, and sees a dog being pulled on a leash.


3/28

3

Upon hearing the word leash for the first time, the child might hypothesize that this term refers

to the leash rather than to the dog, because the dog already has a known category label.

These three constraints might seem obvious to an adult who has already learned a language. Yet

imagine a child trying to learning thousands of category labels without these assumptions

(Quine, 1960). In a relatively simple situation of a girl walking in a park with a dog on a leash,the category label dog might refer to the girl, the park, the dog, the leash, some part of the girl,

the park, the dog, or the leash, or some relation between any of these things. It appears that some

application of general knowledge to this potentially confusing situation would be extremely

helpful and indeed necessary.


4/28

4

ALTERNATIVE CONCEPTS AND MISCONCEPTIONS

Roth (as cited in Fraser, 1995) describes three important approaches to science education:

1) The inquiry approach - in 1960s and 1970s new science programmes were developed to focus

upon the nature and processes of science. The students were to act like scientists and scientific

method was a pivot. Science content was used for learning science process skills;

2) The societal approach - in the late 1970s and 1980s science programmes were used to

inculcate the skills of decision making and problem solving in relation to the societal problems in

order to make the students good citizens;

3) The conceptual change approach - from the mid-1980s science programmes stressed

conceptual change in learning process. A learner has a world view based on personal

observations. The starting point is the childrens prior conceptions. Instructional activities should

be based on the reasoning explicit.Wandersee, Mintzes and Novak (1994) mention that the research on students alternative

conceptions in various content domains rapidly expanded during the 1980s. As surveyed by Duit

(2007) there are over 8000 studies in science education literature that reported the existence of

misconceptions or alternative conceptions.

Numerous studies in recent years have shown proof that many students do not understand

concepts in science in the same way as experts and scientists.

Students incorrect understanding of scientific concepts and natural phenomena affects their

performances.

Smith, DiSessa, and Roschelle (1993) observed that novice interpretations of scientific concepts

and expert perceptions of scientific knowledge are very different.

Tomita (2008) argued:

When students enter science classrooms, they often hold deeply rooted prior knowledge or

conceptions about the natural world. These conceptions will influence how they come to

understand their formal science experiences in school. Some of this prior knowledge provides a

good foundation for further formal schooling, while other conceptions may be incompatible with

currently accepted scientific knowledge. The importance of prior knowledge and the struggle toreplace that knowledge with or help that knowledge evolve into scientifically-sound knowledge

has spurred a large tradition of research in developmental and instructional psychology and

science education (p. 9).

Three examples of science concepts and their associated misconceptions


5/28

5

Scientific Concepts Associated Misconceptions

Whether something sinks or floats depends

on a combination of its density, buoyancy,

and effect on surface tension.

Things float if they are light and sink if

they are heavy.

Clouds contain very small particles of

water or ice that are held up in the air by

the lifting action of air currents, wind and

convection. These particles can become

bigger through condensation and when they

become too heavy to be held up in the air

they fall to the earth as rain, hail or snow.

Clouds contain water that leaks out as rain

An animal is a multicellular organism thatis capable of independent movement.

An animal is a land mammal other than ahuman being. Insects, birds and fish are not

animals.


6/28

6

Importance of weeding out misconceptions

For the authenticity of the knowledge, correct concepts need to be developed and the

misconceptions are to be weeded out. Ausubel (as cited in Joyce, 1996) mentions that a person's

existing cognitive structure is the foremost factor governing whether new material will be

meaningful and how well it can be acquired and retained. Before we present new materialeffectively, we must increase the stability and clarity of our students' structures.

To acquire knowledge of misconceptions of students about certain topics to be taught is

important. Generally, misconceptions are the cause of low achievement. If the number of

misconceptions increases, the students face difficulty in understanding the concept being taught.

Low understanding results in hampering the concept understanding. In some cases alternative

concepts hamper to generalize. As a consequence, meaning of the concept is restricted. In other

cases, students are unable to discriminate among closely related concepts causing them to

mislabel or misclassify.

The history of science has shown that conceptual change is a lengthy process accompanied by astruggle with different types of misconceptions and that it includes alternating stages of advance

and retreat. It is not reasonable to expect our students to internalize the model in a meaningful

manner after it is presented by several statements of knowledge over the course of one or two

class sessions.

Misconceptions may have a positive role. Historical research has shown that even great scientists who

broke new ground in any given area still held misconceptions in other areas or aspects. These

misconceptions may be viewed as essential steps in the evolution of innovative ideas. Prior

misconceptions are the raw materials for critical research which then leads us to higher levels

of understanding.It is also necessary to apply this view to the classroom. Despite the fact that teachers want to

help their students reach the desired conceptions, it is necessary to be tolerant and relate

positively to their misconceptions. These misconceptions may be analogous to childhood

illnesses or problems of adolescence. True, they are not welcomed and we may wish that they

would not exist, but we know that ultimately they have a positive function in human develop-

ment.

The development of the history of science can be perceived as an incomplete dialectic process

(thesisantithesissynthesis; today's conception is tomorrow's misconception). We should

understand the function of misconceptions in student intellectual development in a similarmanner. For this reason, educators should not try to ignore or to declare war on misconceptions,

but should rather focus the class on them. Only in this way can they initiate the desired process

of conceptual change.

"For example, Pascal's and Boyle's comparison of air to wool or to a spring in order to

explain its compressibility or Torricelli's comparison of the atmosphere to an ocean in order to

explain differences of pressure at different altitudes.


7/28

7

Definitions of Misconceptions

Driver, Guesne and Tiberghien (1985) mention that children try to interpret prevailing

phenomenon with previously acquired ideas. An extensive literature has been built up in recent

years, which indicates that children develop ideas about natural phenomenon before they are

taught science in school. Fraser (1995) mentions that every child has ideas to explain thesurrounding world. In many cases these explanations are not the same as given by today's

scientists. Such type of explanation is termed as misconceptions or alternative conceptions.

Misconceptions can be described as ideas that provide an incorrect understanding of such ideas,

objects orevents that are constructed based on a persons experience including such things as

preconceived notions, nonscientific beliefs, nave theories, mixed conceptions or conceptual

misunderstandings.

Misconceptions are the interpretations and understandings that dont support the scientific

reasons or provide footing for the logic.

Despite the fact that the term ofstudent misconceptions is widely used in scientific literature, not

all researchers agree to define students prior knowledge as misconceptions. The term

misconception has many synonyms.

Tomita (2008) summarized synonyms existing in the literature for this term. Primarily referred to

as misconceptions, these conceptions also are called naive conceptions, nonscientific beliefs,pre-

instructional beliefs, intuitive knowledge, phenomenological primitives or p-prims, facets, or

alternative frameworks.

Regardless of terminology, the point is to recognize that a students' prior knowledge is

embedded in a system of logic and justification, although one that may be incompatible with

accepted scientific understanding (Tomita, 2008, p. 10).

Smith, diSessa, and Roschelle (1993) argued that clarification of the terms misconceptions,

alternative beliefs, and preconceptions is necessary:

The prefix to the most common term - misconception - emphasizes the mistaken quality of

students ideas.

Terms that include the qualifier alternative - indicate a more relativist epistemological

perspective.

Students prior ideas are not always criticized as mistaken notions that need repair or

replacement but are understood as understandings that are simply different from the views of

experts

Studentsalternative conceptions are incommensurable with expert concepts in a manner parallel

to scientific theories from different historical periods

Preconceptions and nave beliefs emphasize the existence of student ideas prior to instruction

without any clear indication of their validity or usefulness in learning expert concepts.


8/28

8

However, researchers who have used them have tended to emphasize their negative aspects. This

epistemological dimension emphasizes differences in content. The content of student

conceptions (whether mistaken, preexisting, or alternative) is judged in contrast to the content of

expert concepts (p. 159).

The word misconceptions as used throughout this document may be taken to mean alternativeframeworks or alternative conceptions.) A misconception can be defined as a view that does

not fully coincide with the scientific view.

Categories of misconceptions

National Academy Press (1997) quotes five categories of misconceptions:

1) preconceived notions - many people preconceive that underground water flows in the form of

streams as they have preconceived this idea from their everyday experiences. Such type of

misconceptions is called preconceived notions;2) non-scientific beliefs - some students learn through religious/mythical belief about the origin

of life. The disparity between the religious belief and the scientific belief create misconception;

3) conceptual misunderstanding - students when taught in a way, which does not conflict with

their misconceptions, creates faulty models;

4) vernacular misconception, when words mean scientifically different and in everyday life as

well e.g. work;

5) factual misconceptions - falsities learnt at early ages are not challenged in adulthood. For

example, an idea that lightning never strikes the same area twice if not challenged may be

present in your belief system.


9/28

9

UNDERSTANDING AND CONCEPTUAL CHANGE

IN SCIENCE

To date, science educators have published over 3500 studies on students' understandings of

scientific concepts.

In contrast to the assumptions of many science teachers, it is now clear that learnersdevelop a set of well-defined ideas about natural objects and events even before they arrive

at the classroom door. These ideas span the range of the formal scientific disciplines and

seem to be found in equal frequencies among males and females, learners of all ages and

ability levels, as well as cultural backgrounds and ethnic origins.

Often these notions conflict with accepted scientific explanations and, most significantly,

because they serve a useful function in everyday life, they tend to resist the efforts of even

our finest teachers and most thoughtful textbook authors and curriculum developers.

Unfortunately students' ideas often interact with knowledge presented in formal science

lessons resulting in a diverse set of unintended learning outcomes.

Assumptions about Misconceptions

1.Learners are not "empty vessels" or "blank slates"; they bring with them to their formalstudy of science concepts; a finite but diverse set of ideas about natural objects and

events; often these ideas are incompatible with those offered by science teachers and

textbooks.

2.Many alternative conceptions are robust with respect to age, ability, gender, andcultural boundaries; they are characteristic of all formal science disciplines including biology,chemistry, physics, and the earth and space sciences; they typically serve a useful function

in the everyday l ives of individuals.

3.The ideas that learners bring with them to formal science instruction are oftentenacious and resistant to change by conventional teaching strategies.

4.As learners construct meanings, the knowledge they bring interacts with knowledgepresented in formal instruction; the result is a diverse set of unintended learning outcomes;

because of limitations in formal assessment strategies, these unintended outcomes may

remain hidden from teachers and students themselves.

5.The explanations that learners cling to often resemble those of previous generationsof scientists and natural philosophers.

6.Alternative conceptions are products of a diverse set of personal experiences, includingdirect observation of natural objects and events, peer culture, everyday language, and the

mass media as well as formal instructional intervention.

7.Classroom teachers often subscribe to the same alternative conceptions as their


10/28

10

students.

8.Successful science learners possess a strongly hierarchical, cohesive framework ofrelated concepts and they represent those concepts at a deeper, more principled level.

9.Understanding and conceptual change are epistemological outcomes of the consciousattempt by learners to make meanings; successful science learners make meanings byrestructuring their existing knowledge frameworks through an orderly set of cognitive events

(i.e., sub-sumption, super ordination, integration, and differentiation).

10.The differential ability to solve problems in novel, real-world settings is attributableprimarily to the advantages conferred on individuals possess ing a highly integrated, well-

differentiated framework of domain-specific knowledge which is activated through

concentrated attention to and sustained reflection on related objects and events.

11.Learners who excel in the natural sciences habitually employ a set of metacognitivestrategies enabling them to plan, monitor, regulate, and control their own learning.

12.Instructional strategies that focus on understanding and conceptual change may beeffective classroom tools.

Research-based claims relating to authentic alternative conceptions

Claim 1: Learners come to formal science instruction with a diverse set of alternative

conceptions concerning natural objects and events. Alternative conceptions span the fields from

physics and earth & space science to biology, chemistry, and environmental science. Each

associated subfield within the disciplines seems to have its alternative conceptions.

Claim 2: The alternative conceptions that learners bring to formal science instruction cut across

age, ability, gender, and cultural boundaries. No matter how gifted a group of students

concerned, each group will have students with alternative conceptions regardless of background.

Claim 3: Alternative conceptions are tenacious and resistant to extinction by conventional

teaching strategies. Students alternative conceptions are very difficult to change; only very

specific teaching approaches have shown promise of getting students to accept new explanations.

Claim 4: Alternative conceptions often parallel explanations of natural phenomena offered by

previous generations of scientists and philosophers. Students often hold to the same views as

those held by very early scientists that are frequently referred to as Aristotelian in nature.Claim 5: Alternative conceptions have their origins in a diverse set of personal experiences

including direct observation and perception, peer culture, and language, as well as in teachers

explanations and instructional materials. The many sources of alternative conceptions are at best

speculative, but research and inference suggest that a students worldview is strongly influenced

by his or her social environment.


11/28

11

Claim 6: Teachers often subscribe to the same alternative conceptions as their students. It is not

at all uncommon for science teacher educators to see alternative conceptions in their teacher

candidates; likewise, even experienced science teachers and scientists with advanced degrees

will sometimes cling to alternative conceptions that are held by their students.

Claim 7: Learners prior knowledge interacts with knowledge presented in formal instruction,resulting in a diverse variety of unintended learning outcomes. Not only can alternative

conceptions be a hindrance to new learning; they can also interact with new learning resulting in

mixed outcomes. It is not unusual to see different students draw different conclusions from the

same experiences and observations.

Claim 8: Instructional approaches that facilitate conceptual change can be effective classroom

tools. Several conceptual change approaches have been developed to identify, confront, and

resolve problems associated with alternative conceptions.

Some features of misconceptions are that they:

nd are usually adequate for everyday life;

ht in schools;


12/28

12

Sources of students misconceptions

Students develop certain misconceptions since science is being taught as a historical account.

Demonstrations, observation and experimentation find a little space in the teaching of science.

The content teaching is not supported with the practical experimentation.

Driver (1985) mentions that the possible sources of students misconceptions are: schoolteaching, outside school teaching, everyday experiences, social environment, and intuition.

Nonetheless, there is general evidence that pre-instructional knowledge structures have their

origins in the following sources: (1) experiences and perceptions that extend as far back as early

infancy, (2) a wide variety of cultural values and ideas, and (3) language factors.

Experiences and perceptions: Hawkins and Pea (1987) argue that children construct knowledge

structures for scientific understanding on a domain by domain basis prior to formal instruction.

It is therefore important to view children as active constructors of knowledge through their

interactions with the physical world and their social and cultural environments. Even when they

are only toddlers, children are actively engaged in asking for explanations and giving reasons

about the way things are. A functional reason for developing these explanations is to gain more

predictive control over the world. This allows the child to avoid undesirable events and to

perpetuate desirable ones. The child learns what to expect by his own actions, by the actions of

others, and by events in the physical world. In this way, children construct non-scientific

understandings of natural phenomena as they are encountered, and they create frames for

interpreting natural and social events. Further insights are provided by McClelland (1984):

Phenomena are not the content of science but the vehicle for learning it, that is, for learning

theories. Children in all societies meet a wide range of phenomena but a glance at history and

anthropology is enough to remind us that interpretations in terms or reproducible, explicable,causally related events are not automatic features of human thought.

Pre-instructional understandings are therefore quite adequate to interpret and guide daily life

(Driver, 1994), but may significantly hinder learning in the context of the science classroom.

Culture: Conceptions can also have their origin within the overall culture that students are

participants in. Solomon (1987) states that the social scene makes an essential difference as to

how a particular task is perceived in the learning environment.

He therefore asks, Do entirely personal ideas ever exist? When a child holds some private

evaluation about a scientific happening, is it ever unaffected by culture?

Solomon argues that even if a student has a truly eccentric idea, this idea will probably will not

survive for very long. Too different of a viewpoint from the accepted notion will generally be

excluded from social intercourse, and many children may not have the ability to withstand this

kind of pressure. The human desire to be accepted will cause many individual ideas to fade

away. The chief effect of social interaction, therefore, is to


13/28

13

smooth out differences within the culture and to produce consensus. This is not to say that

change cannot take place; even majority views change with time. However, it is to say that the

influence of the overall culture on students understandings is incredibly powerful and cannot be

ignored by instructors.

An example of how cultural influences can effect understanding is found in a study thatexamined folk biological taxonomies among the Itzaj (a people native to the Americas) and

among North American college students (Lopez 1997). Of special interest was the way that the

Itzaj subjects categorized bats. While the American group tended to group bats with insectivores

and rodents (thus preserving scientific formalisms to a significant degree), the Itzaj left them

unaffiliated with any general category, or they classified them as birds. When asked, the Itzaj

acknowledged that bats do indeed seem to more closely resemble shrews and small rodents.

They did not classify them as mammals, however, because they knew that bats are birds!

Cultural influences caused the Itzaj subjects to deem the relationship of bats to mammals as

superficial. The influence of scientific understanding on the culture of the United States,

however, helped the North American college students to avoid this stumbling block.

Language: Word meaning and usage can also be a significant source for alternative conceptions.

An example of how this can happen is presented by Strike and Posner (1992). They describe a

hypothetical learner named Fred who is asked to choose between two views of motion. Fred is

asked to think about what will happen if a force is applied to a particular object. He is presented

with two views:

(1) Force is transferred to the object and erodes, causing the object to gradually slow and

eventually come to a rest.

(2) Application of force to the object imparts some motion to the object that continuesindefinitely until it is acted upon by another force.

Fred is a baseball fan and he notes that there are numerous cases where forces are applied to

baseballs. The subsequent motion of the balls leads him to accept the first view. This seems

logical to Fred because he can detect no other forces being applied to the baseballs.

Thus begins the language game. Strike and Posner explain it in the following way:

Fred may have learned to talk about force in a way that requires force to have an agent. Hitting

balls with bats thus counts as applying force. Also, force-talk may be associated with fatigue.

Ones ability to apply force is limited by stamina. Or sometimes in ordinary speech force is

associated with coercion. Normally, when people are coerced, they cease doing what they arecoerced to do as soon as the coercion is withdrawn. Fred thus has ways of talking about force

that lead to and reinforce a way of seeing.

Fred thus decides that forces are transferred to objects and erode during motion.

This story may only be hypothetical, but it is a very realistic illustration. Indeed, studies

involving both grade school and college level students have demonstrated that students often do


14/28

14

not have the same definitions for scientific terms as those that are held by their instructors. For

example, a general characterization of nave knowledge of motion has been described as follows

(Champagne 1983):

(1) Concepts are poorly differentiated. For example, students use the terms speed, velocity and

acceleration interchangeably. As a result, the typical student does not perceive any differencesbetween two propositions such as these: (a) The speed of an object is proportional to the [net]

force on the object; (b) The acceleration of an object is proportional to the [net] force on the

object.

(2) Meanings physicists attribute to terms are different from the everyday meanings attributed to

the terms by the students. For example, students generally define acceleration as speeding up,

while physicists define acceleration as any change in velocity.

According to some psychologist, there are some other possible sources for the development of

misconceptions. First, not all experiences lead to correct conclusions or result in students seeing

all possible outcomes. Second, when parents or other family members are confronted withquestions from their children, rather that admitting to not knowing the answer, it is common for

them to give an incorrect one. Other sources of misconceptions include resource materials, the

media and teachers. The main issue is that all of the above sources are considered to be

trustworthy, leading to ready acceptance by students of what they are being taught

why some science concepts are difficult to change?

In fact, there is overall consensus among researchers that alternative conceptions about science

are highly resistant to change (MacBeth 2000). Simply telling somebody something does not

easily change his or her deep ideas (Redish 1994). One researcher went so far as to say that

we cannot affect scientific understanding without grasping the depth and tenacity of the

students preexistingknowledge.

Chi (2005) mentions why some science concepts are difficult to change? He explains that

students own ontological categories and the actual categories do not correspond. Member of one

ontological category is misrepresented as a member of another ontological category.


15/28

15

Misconceptions in Science

Brown and Hammer (2008) described a typical example of students misconceptions about

scientific concepts (in physics). A student may be able to apply F = ma accurately to find a if

given F and m, but if asked to explain what the equation means might say something like: It

means that the force of an object depends on how heavy it is and how fast its moving. Thisinvolves alternative ways of thinking about all three variablesforce as a property of an object,

mass as weight, and acceleration as speed (p. 128). Brown and Hammer (2008) argued that even

after physics instruction, college graduates continue to have serious misconceptions about

various concepts like force, energy, and temperature. Even the best and brightest students are not

learning what educators may think they are learning from their science education.

There is a wide range of literature about misconceptions in science, which often discusses the

understandings of physical phenomena by students. Incorrect (unscientific) perceptions are

called misconceptions. There are a few stages that the majority of literature follows:

- Describe a phenomenon (like force, temperature, light).

- Ask students what they think about this phenomenon, what will happen and why.

- Analyze the answers (correct and incorrect perceptions of the phenomenon).

- Make an attempt to understand how the incorrect meaning of the phenomenon occurs. Refer to

cognitive psychology and conceptual change theories.

- Discuss robustness of student misconceptions.

- Discuss how to improve the curriculum and teaching methods.

Streveler et al. (2008) argued that one of the main issues in psychology literature about

conceptual knowledge is whether the students' knowledge is organized in a coherent structure or

whether it is fragmented (p.280). Therefore, the literature often considers s tudent

misconceptions from two perspectives, alternative ideas that are organized as theory or ideas that

are elements or fragments. Brown and Hammer (2008) argued that these two perspectives on

misconceptions shifted educators understanding of student errors:

Whereas previously students were seen as just making mistakes, now they were seen as scientists

applying alternative theories to interpretations of phenomena. This helped to make sense of why

students seemed resistant to new ideas and it drew attention to the need to understand their

existing theories (p. 130).

Methods to help the students to overcome misconceptions

The teacher can try the following methods to help the students to overcome misconceptions.

1. Anticipate the most common misconceptions related to the instructional material.


16/28

16

2. Encourage students to test their conceptual frameworks after discussing with the other

students.

3. The teacher should think about the demonstrations for addressing the common

misconceptions.

4. Assess whether the students have been able to grasp the concept according to the scientistbelief or not?

Biemans mentions that prior knowledge activation and conceptual change can be fostered by a 5-

step strategy:

1) searching for ones own preconceptions;

2) comparing and contrasting these preconceptions with new information;

3) formulating new conceptions based on previous steps;

4) applying new conceptions; and

5) evaluating the new conceptions based on previous study.

The precursor mentioned in these strategies are used to bring about conceptual change are the

knowledge of misconceptions.

Pedagogies for Addressing Alternative Conceptions

A wide range of pedagogies has been developed to address alternative conceptions such as

learning cycles (Karplus, 1981), Conceptual change theory of Posner et al. (1982), bridging

analogies (Clement, 1988; Perschard & Bitbol, 2008), microcomputer- based laboratoryexperiences (Thornton & Sokolof, 1990; Thornton, 1987), disequilibration techniques (Minstrell,

1989; Dykstra, Boyle, & Monarch, 1992), an inquiry approach coupled with concept substitution

strategies (Harrison et al., 1999), metaconceptual teaching on inducing a particularly problematic

aspect of the conceptual changes (Wiser & Amin, 2001), and a teaching model (Thomaz et al.,

1995).

These approaches tend to have in common the requirement that students encounter phenomena

that run counter to their existing beliefs. Doing so, they are put in a state of intellectual

disequilibrium or cognitive conflict. Becoming aware of the conflict between what they believe

to be correct based on prior experiences and know to be correct based on more recent experience

helps them to confront and resolve their conflicting perspectives in favor of a proper

understanding. Such pedagogical approaches that emphasize conflict and resolution appear to

derive from a Piagetian perspective on learning (Scott, Asoko, & Driver, 1998). In such a

viewpoint, the learners role in reorganizing their knowledge is central to overcoming the

alternative conception.


17/28

17

These and other approaches dealing with alternative concepts typically include three

fundamental stepsthose identified by the University of Washington Physics Education Group:

elicit/ confront/resolve (McDermott, 1991). In this model a teacher first elicits a response

(prediction about what will happen or an indication of agreement or disagreement with a given

statement) from students, forcing them to commit to an answer in relation to a specific situation.

Next, the students confront a situation that challenges their beliefs and answers, typically in an

experiment that the students perform. During this second phase, if the students were incorrect in

their prediction, they experience cognitive dissonance when confronting the conflict between

prediction and experience.

Students quickly come to realize the need for a new understanding about the concept under

consideration, and are motivated to resolve the conflict with teacher assistance in phase three.

Another such strategy is that developed for the C3P Project. According to Olenick (2008)

overcoming alternative conceptions requires the following distinct steps:

(1) Teachers must recognize that alternative conceptions exist.

(2) Teachers probe for students alternative conceptions through demonstrations and questions.

(3) Teachers ask students to clarify their understanding and beliefs.

(4) Teachers provide contradictions to students alternative conceptions through questions,

implications, and demonstrations.

(5) Teachers encourage discussion, urging students to apply physical concepts in their reasoning.

(6) Teachers foster the replacement of the misconception with new concepts through (i)

questions, (ii) thought experiments, (iii) hypothetical situations with and without the underlying

physical law, and (iv) experiments or demonstrations designed to test hypotheses.

(7) Teachers reevaluate students understanding by posing conceptual questions.

The Focus of Conceptual Change Research

In a previous section, I demonstrated why one who simply learns that it is raining outside (or that

hot air rises, or that anything else happens for that matter!) has not necessarily undergone what

researchers within the conceptual change domain consider to actually be conceptual change. It

has been shown that ideas held by learners are rooted within a lifetime of experiences,

perceptions, cultural influences, and language use, and cannot be easily overthrown. As such, itseems inadequate to attempt to change, idea by idea, the vast inventory of alternative

conceptions. It is important to understand that conceptual change research is performed by

people who are heavily involved in the science education system, and who are searching for

solutions for its crucial problems and inadequacies (Anderson 1987). As such, the futile

endeavor of altering the plethora of individual ideas is rejected. Instead, conceptual change

researchers focus their attention on those concepts that are at the core of a system of concepts.


18/28

18

It is more analogous to what Piaget calls an accommodation, or to what Kuhn calls a paradigm

shift (Strike 1992). The next two paragraphs present a brief overview of both of these ideas.

Accommodation: Piagets notion of an accommodation involves the replacement or

reorganization of central concepts (Posner 1998). The easiest way to explain what is meant by

this is to give a couple of examples. I will begin with a simple one (Millhoff 2002): Sometimes old ways or existing schemes of dealing with the world simply dont work. Piaget used the

term accommodation to describe this changing of an existing scheme to fit new objects. An

example of accommodation would be the action of a young person who has always ridden a

bicycle with pedal brakes but then gets on one with hand brakes.

Accommodation of the existing braking scheme must occur for the bicyclist to be able to stop.

A more complex example from Piagets own writings involves a four month and twentytwo day

old infant named Laurent (Piaget 1952): Laurent knows how to strike objects intentionally

with his hand [He] holds a stick; he does not know what to do with it and slowly passes it from

hand to hand. The stick then happens to strike a toy hanging from the bassinet hood. Laurent,immediately interested by this unexpected result, keeps the stick raised in the same position, then

brings it noticeably nearer to the toy. He strikes it a second time. Then he draws the stick back

but moving it as little as possible as though trying to conserve the favorable position, then he

brings it nearer to the toy, and so on, more and more rapidly [The] child, intentionally and

systematically, applies himself to rediscovering the conditions which lead him to this unexpected

result.

Paradigm shift: Kuhns notion of the paradigm involves concepts that are organizing in nature,

and that adequately address contemporary research problems. In his bookThe Structure of

Scientific Revolution (1970), Kuhn describes the history of science as a series of paradigm shifts.If the dominant paradigm of the time cannot adequately address contemporary problems, a new

paradigm may arise and compete for acceptance. Normal Science therefore involves research

that is firmly based on one or more scientific achievements that some particular scientific

community acknowledges, for a time, as supplying the foundations for its future research and

practices. However, even if the new paradigm proves better at problem solving, it is often met

with resistance. Many scientists will adhere to the old paradigm until their deaths even if it

means ignoring a tremendous amount of evidence. Copernicanism, for example, was not widely

receivedby the scientific community until nearly a generation after Copernicus death.

5. Examples of Conceptual Change Research

When a learner makes a conceptual leap that is analogous to an accommodation or paradigm

shift, then one can say that conceptual change has finally taken place within that learner. It is

around this notion that theories of conceptual change are designed.


19/28

19

Metacognition and Conceptual Change

RICHARD F. GUNSTONE

Monash University

IAN I. MITCHELL

Monash University andEumemmering Secondary College

Our meanings for conceptual change and metacognition

Some general research influences underpinning the growth of concern with conceptual change

have been described in Chapter 3 of this volume (Section 3: "Understanding and

Conceptual Change in Science: The Current Research Agenda"). These influences have been

of fundamental importance to the evolution of our own ideas. Our work in this area over the

past 15 years has been largely in physics (e.g., Gunstone & White, 1981) and chemistry

(e.g., Mitchell & Gunstone, 1984). Much of this work has been located in, and therefore

intertwined with, the dailiness of our normal teaching in high school science (e.g., Baird &

Mitchell, 1986; Baird & Northfield, 1992; Mitchell, 1993; White & Mitchell, 1994) and teacher

education (e.g., Champagne, Gunstone, & Klopfer, 1985; Gunstone, 1994; Gunstone &

Northfield, 1994). Our concerns throughout this work have been to develop our

understanding of conceptual change and metacognition in the context of normal school and

university classrooms.

Conceptual Change

One significant aspect of our current conception of conceptual change is that the content to

be learned is a major variable in terms of the process of conceptual change (Mitchell &

Baird, 1986; White, 1994). We return to this point in the concluding section of the chapter and,

for the moment, consider conceptual change in more general terms.

When considered in terms of an individual learner, the essence of a constructivist view of

conceptual change is that it is the learner who must recognize his/her conceptions, evaluate

these conceptions, decide whether to reconstruct the conceptions, and, if they decide to

reconstruct, to review and restructure other relevant aspects of their understanding in ways

that lead to consistency. While ultimately these processes of recognize, evaluate, decide

whether to reconstruct, review other aspects of understanding are individual, each is

profoundly influenced (positively or negatively) by the ways in which the teacher, and other

class members, structure classroom practice.

These processes of recognize, evaluate, reconstruct, and review do not often lead to

dramatic conceptual change. Conceptual change is rarely a sharp replacement of

conception X by conception Y. Rather, conceptual change is more often "an accretion of

information that the learner uses to sort out contexts in which it is profitable to use one form


20/28

20

of explanation or another" (Fensham, Gunstone, & White, 1994, p. 6).

Mitchell (1993) studied the learning of all students in four Grade 10 science classes

during a 6-week unit on mechanics, a unit very similar to the sequence we describe below.

He began this research looking for, and expecting to find, numerous examples of "ahha"

experiences/incidentsthat is, experiences/incidents that were crucial to the conceptualchange of individual students. Although almost all students could on completion of the

unit identify lessons and specific experiences that they had not found personally useful, there

was only a very small number of "ahha" experiences. Most students found that most lessons

made some useful contribution to their learning. Their conceptual change was evolutionary

rather than revolutionary. This can be explained by the view of Hewson and Hewson (1992)

that conceptual change involves a change in the status of competing ideas. The new ideas

(Newtonian in this mechanics case) appeared to need a number of successful classroom

episodes in order to gain the status of unquestioned superiority.

It is often appropriate to consider the process as "conceptual addition" rather than

"conceptual change."

The example of drinking through a straw illustrates the point about shifts as well as

additions in meaning. When learners come to understand the notion of pressure

difference, they do not drop the word "suck," though their conceptions of sucking

change. Knowledge about pressure has been added, but old kno wledge is revised

rather than abandoned. A conceptual addition has occurred. Central to this formula-

tion of what is often described as "conceptual change" is that the individual also has

informed approaches to deciding which of a number of meanings is appropriate in aparticular context.

(Fensham, Gunstone, & White, 1995, p 7; emphasis added)

A further significant aspect of conceptual change, a term we continue to use in this

chapter because it is so widespread as a general description for the development of

understanding, is also related to contexts. Often learners will accept the scientific concept in

one context, but then revert to using their prior conception in another context that we as

science teachers would see as essentially the same as the first context. That is, conceptual

change can often be seen to first take place in a particular context. Then the student may

vacillate between scientific and prior conceptions from one context to another; the

conceptual change is then context dependant and unstable. Long-term and stable

conceptual change is achieved when the learner recognizes relevant commonalities across

contexts and the generality of the scientific conception across these contexts (Tao, 1996; Tao &Gunstone, 1997).

Metacognition

Our conception of metacognition has been formed through research in classrooms (ours and

others). It is a multifaceted conception, described in a number of sources (e.g., Baird &

Mitchell, 1986; Baird & Northfield, 1992; Gunstone & Northfield, 1994; Mitchell, 1993;


21/28

21

White & Mitchell, 1994). We now give a brief summary (based on Gunstone, 1994, pp. 134-

136) of the various and complementary aspects of our meaning for metacognition.

1. "Metacognition refers to the knowledge, awareness and control of one's own

learning" (Baird, 1990, p. 184). Metacognitive knowledge refers to knowledge of the nature

and processes of learning, of personal learning characteristics, and of effective learningstrategies and where to use these. Metacognitive awareness includes perceptions of the

purpose of the current activity and of personal progress through the activity.

Metacognitive control refers to the nature of learner decisions and actions during the

activity. Inadequate knowledge restricts the extent to which awareness and control are

possible.

2. Metacognitive knowledge, awareness, and control are all learning outcomes(as well as fundamental influences on the nature of more usual learning

outcomes). Hence metacognitive knowledge, awareness, and control can be

developed with appropriate learning experiences. (This is well illustrated by

extensive work in the Project for Enhancing Effective Learning (the PEEL project);

see Baird & Mitchell, 1986; Baird & Northfield, 1992).

3. Often the learning which gives rise to a learner's metacognitive ideas andbeliefs has been unconscious learning, and the learner finds it difficult to

articulate his/her metacognitive views.

4. All learners have metacognitive views of some form. That is, all learners havesome form of metacognitive knowledge. This can be of a form that is in conflict

with the goals of conceptual change teaching (e.g., "it is the teacher's job to tell me

so I understand"; "we have discussions in science when the teacher can't bebothered teaching"). There are many examples of such conflict (see, for example,

Baird & Mitchell, 1986; Baird & Northfield, 1992).

5. There can be tensions between metacognitive knowledge, awareness, andcontrol. Most obvious are contexts where the assessment of learning is via rote

recallhere learners with enhanced metacognitive knowledge and awareness will

see that they should not invest time and effort in developing their understanding

and controlling their learning if they wish high grades. Teaching concerned with

conceptual change and enhanced metacognition must have assessment

approaches consistent with these learning goals.

6. One helpful description of an appropriately metacognitive learner is alearner who undertakes the tasks of linking and monitoring their own learning.

7. There are a number of commonly occurring poor learning tendenciesexhibited by many learners (Baird, 1986). Examples are superficial or impulsive

attention, premature closure (where "closure" is used here and at other points in

this chapter to mean bringing together in a conclusion; "premature closure" is then


22/28

22

concluding or deciding that the task is complete before this is appropriate), lack

of reflective thinking, and staying stuck (i.e., one problem or error stops all

progress). These represent inadequate metacognition and are major barriers to

learning.

8.On the other hand, there are good learning behaviors which illustrate more

appropriate metacognition in classrooms (Baird & Northfield, 1992, p. 63);

these good learning behaviors can be fostered by appropriate teaching.

These behaviors are many. Examples include telling teacher what they don't understand,

planning a general strategy before starting a task, seeking links with other activities or

topics, and justifying opinions.

The Intertwined Nature

of Conceptual Change and Metacognition

The links between conceptual change and metacognition seem to us an obvious

consequence of our description of conceptual change. The processes of recognizing existing

conceptions, evaluating these, deciding whether to reconstruct, and reviewing are all

metacognitive processes; they require appropriate metacognitive knowledge, awareness, and

control.

We now give an outline of a teaching sequence that is derived from these conceptual

change/metacognition perspectives, beginning with some as pects of the broad intent of

the sequence. After the outline we discuss some more general aspects of classrooms that

are relevant to the sequence.

AN EXAMPLE OF TEACHING

FROM THESE PERSPECTIVES

The sequence we describe below is about introductory mechanics. The sequence has been

shaped by research on students' alternative conceptions in mechanics and by the views of

conceptual change and metacognition outlined above. We have taught the sequence on a

number of occasions, and reflections on these experiences have contributed to the form

given here. Our own uses of the approaches in this content area have largely been with

Grade 10 high school students in the state of Victoria (where science in Grades 7-10

of the 6-year high school is a General Science taken by all students) and with science

graduates who are Biology majors undertaking a 1-year postgraduate course to qualify

as high school science teachers (and who may therefore be required to teachintroductory mechanics in the General Science program). We describe the sequence in

terms of a Grade 10 class. We do not give fine detail in our descriptionclass, school,

and curriculum contexts vary; so then will the fine detail of the sequence.

The sequence begins with the probing of students' existing ideas, then seeks to

promote the reconstruction of ideas about particular content, then explicitly considers the


23/28

23

exploration of the consistency ideas across a variety of contexts, and finally concludes

with some ideas for the assessment of learning from the sequence. It uses a range of

experiences to foster students' intellectual engagement with the ideas to be learned. We

assume throughout that much of the language that students use will be tentative,

exploratory, and hypothetical as they grapple with the ideas of mechanicsthis

assumption is a consequence of our recognition that students need time to consider and

discuss these ideas if they are to develop understanding. We also assume that there

will commonly need to be risk taking on the part of both learners and teachers.

Throughout the sequence there should be an emphasis on the creation of links between

lessons and with experiences students bring to the classroom and on the central issue of

the consistency of students' views across situations. It is intended that students will

learn from the questions and ideas and exploratory language of other students and that

the rate of progress through the sequence (and some of the detail of the sequence per

se) will be influenced by students and their ideas.

The sequence includes three teaching approaches that may be unfamiliar: predict-

observe-explain (POE); concept maps; relational diagrams (or Venn diagrams). We give a

very brief description of the nature and intent of each of these here. Space prevents our

giving a comprehensive account of the range of ways each of these approaches can be

used, and of the linkages between these approaches and student learning. Such an

account is in White and Gunstone (1992).

Predict-Observe-Explain (POE)

Students are shown a real situation, asked to give their prediction about the consequences

of a particular change to the situation and the reasons they have for their prediction,then when the change is made they give their observation, and finally predictions and

observations are reconciled if necessary. POEs can be used to explore students' ideas at

the beginning of a topic, or to develop ideas during a topic, or to enhance understanding

at the end of a topic by having them attempt to apply their learning to a real situation.

In all of these uses, the reasons students have for a prediction are crucial; predictions,

reasons and observations are usually best written, not verbal.

An example of a POE for the content a rea of heat capacity of materials: The situation

is a beaker of water and a beaker of cooking oil (equal volumes of liquids) placed on a

hotplate and with thermometers (0-200C.). Students are asked to predict how the

temperatures of the two liquids will compare when the hot plate has been turned on

long enough for the water to be boiling (it is helpful to give alternatives for students

to choose"Is the temperature of the cooking oil less than, the same as, greater than the

boiling water?"), and to write their reasons. The observation is the readings of the

thermometers. Reconciliation commonly involves addressing their prediction that the

cooking oil temperature is less than the boiling water be cause the oil is not burning.


24/28

24

Concept Maps

Students have a set of words representing concepts, and perhaps other relevant things, and

put these on a sheet of paper. They draw lines between those words that they see to be

linked, and write the nature of the links on the lines. (This last point is crucial; it is the

nature of the links students perceive that is the essence of the concept map.) Usually theteacher provides the students with the terms to be mapped, although there are a number of

reasons for students themselves to sometimes generate some or all of the terms. Concept

maps are highly effective for exploring the links students perceive between ideas, and for

fostering further linking. (See Chapter 3 of this volume for description and examples of

concept maps.)

Relational (or Venn) Diagrams

Students are given a small number of terms and asked to draw a circle or rectangle for each

term, arranged so that the shapes represent the relationships between the terms. An example is

"trees, grasses, flowering plants." The appropriate response has the shape for grasses totallywithin flowering plants, and that for trees partially within and partially without flowering

plants.

There are two important issues to recognize in using each of these three approaches,

particularly concept maps and relational diagrams.

I . Students need to be taught how to approach each of these if the students have not

experienced them before. It is rather like having a class who have never seen multiple choice

questionsbefore you give multiple choice to such a class you would need to help them

understand the structure and intent of the questions, and how to respond. Failure to do this

would mean that students would be unable to respond in the ways you intend. This is less of anissue for POEsthese are sufficiently similar to conventional science demonstrations that

students will not have great difficulty in seeing what they are required to do, but it is a very

important aspect of introducing concept maps or relational diagrams to a class who have not

previously experienced these.

2. It really is important to try any particular examples of the three approaches yourself

before you use these with a class. With concept maps and relational diagrams in particular, this

"trialling" is a necessary step in considering what terms should be given to the students. For

example, we have been using concept maps in our science teaching for over a decade. Yet

we still find that our first list of terms to give to students as a concept mapping task isfrequently changed when we try the task ourselves. That is, often when we do the concept

map ourselves we see that one (or more) terms should be replaced by others for the task to

achieve what we intend.


25/28

25

A CONCLUDING COMMENT

ON INTRODUCING THESE APPROACHES

The approaches we suggest assume major changes for students and teachers, by comparison

with a traditional, didactic classroom. We offer now some thoughts, derived from research and

practice, on the nature of student change required. This is a crucial issue for action, for boththose wishing to introduce these approaches to their classrooms and for those who wish to

research the consequences of these approaches. Note that the points we now briefly make are

elaborated, with data, in many aspects of the PEEL project (Baird & Mitchell, 1986; Baird &

Northfield, 1992; Mitchell, 1993).

Moving from didactic classrooms to the classrooms involved in our mechanics sequence

involves changes in students' metacognitive knowledge, awareness, and control. Put another way,

changes are involved in students' ideas about learning (e.g., discussion can be "real work,"

considering mistakes can contribute to learning), attitudes toward learning (e.g., there is benefit

to my learning in investing the effort needed to engage with tasks and in taking risks by publicly

expressing a point of view), and learning behaviors (e.g., asking questions about issues that are

puzzling). One substantial difficulty in fostering these changes is that it is often quite impossible

to meaningfully describe to students what the benefits of the changes will be before starting to

teach in this manner. It is necessary to slowly build towards the changes through successive

classroom experiences and to reward (via the nature of assessment) the consequences of students

engaging intellectually in the ways we describe. Regular, short debriefing of successful

experiences in terms of the nature of the learning behaviors (e.g., pointing out the value to the

development of ideas by the class of a "wrong" answer that raised an important issue) is one

important component of strategies for achieving this student change. Another was referred to

in 6.2.2 of our mechanics sequence.

It is common for teachers who are first hearing about or reading about these ideas to be

sceptical. We frequently experience such reactions in our professional development work with

other teachers, with comments about classroom management and content coverage often

being made. The issue of content coverage has already been discussed; classroom

management is not an ongoing issue when students are genuinely engaged. Our approaches

have been used by many teachers, and the PEEL project (already frequently referred to in this

chapter; Baird & Mitchell, 1986; Baird & Northfield, 1992) provides many classroom examples

of these approaches. We reinforce this assertion of the feasibility of our approaches by

concluding with an extract from a class disscussion in one of our classes. The class is a Grade10 in an average government high school.

Two views of whether or not a table pushes up on a book placed on it have already been

advanced: the table does not push up, initially advanced by Katie ("The table does not push

up on the book, it just stops it falling; a table can't push"); the table does push up with a

force equal and opposite to gravity, initially advanced by Ward. Other students have

advanced arguments to support one of these views. The teacher has set up a meter ruler


26/28

26

supported at either end and with weights placed at the middle of the ruler as an example of

a much more flexible "table." (This is in 5.1 of the above sequence.) The extract begins with

Ward commenting on the meter ruler demonstration. Comments in italics were inserted by the

teacher to provide explanation of his thinking and decisions.

Ward:The ruler is pushing up, it's like a spring, because when you put itthe weight( on it, it's like you've loaded a spring. If you took it off it's

going to spring back up.

(This comment could lead to the class working out how a table can push up. I wa nt

it noted, but I don't want to reveal my views yet.)

Teacher:So you reckon because it's bent it's pushing back up?

II am extracting neutrally whatIsee as the key new point Ward is making.]

Ward: Yes.

Brad:If it was pushing up, wouldn't it be straight?

'Brad is reacting to Ward's views. His argument is a common one. Brad cannot

(yet) picture the ruler pushing up and not moving up. This issue is central and I

want it thought through. I respond to Brad similarly to how I responded to Ward.

Teacher:If it's pushing up wouldn't it be straight ... so you're saying it's not

pushing up at the moment because it's bent?

Brad and Kay:Yeah.

Ward:'interrupts' It must be pushing down with the same power as it'spushing up.

Teacher:So you're saying gravity is pulling down and the ruler's pushing

up

Danielle:'interrupts] If it was pushing down the same as it was pushing up

the ruler would be straight.

I Danielle now introduces a new possibility. I want everyone to be clear on what itisso I draw a diagram

of her view beside the summary of the views ofWard andKatie that I drew earlier. Danielle's view, that

there must be some upwards force, may be very useful in moving toward Newton's Third Law.]

Teacher:All right. So Danielle's argument is ... they can't be equal and

opposite because the ruler would not be bent.

Danielle:It could be a force going up and bigger force going down.

Teacher:OK. So you're prepared to accept some upward force, but it must


27/28

27

be less than gravity down, so your drawing of this one, Danielle, would be

'Teacher draws diagram'. You're prepared to accept that (points to an

upward force) but because the ruler's bent, this one (the downwards

force) must be bigger.

Ward:If there was more force pointing down, then why isn't it going down?Kay and Danielle: 'interrupting) But it hasit has gone down.

This is the start of a sequence of student-to-student debate where Idon't even need to maintain a

chairperson role. The students are very involved and interested. I

Ward:But it's notit's not moving down, what I mean is it's not moving

now. So if there's still more force pushing down, then it's not still going

down.

Danielle:But it can't be equal.

Brad:But it's like adding more weight on the floor. It can't go down any

further.

Ward: Why not?

lames:Because he hasn't got any more weights. I Not a very useful comment.)

Ward:If there's still more force pushing down, why can't it bend?

Brad:Because this is the baseyou knowI mean if you stick the books

on the table they're not going to push the table under the ground. I Brad

believes that the rigid floor does not need to exert an upwards force to prevent weights placed on it frommoving downwards.)

Ward:The table would just push back up again.

Kay:Anyway if you put those weights on this table 'points to a class-

room table) they're not going to go down.

Danielle:No, but if you put heavier things on it, it might.

I Kay may be getting convinced by Ward. She raises the important point that we have achieved little by

showing a ruler table bends under a weight unless we can also show that "real" tables bend. I intend to

show this later by standing students on tables. I don't want to discourage Kay, but I do want to stop the

discussion becoming too complex by dealing with two sorts of tables at onceDanielle has made a good

point. I decide to intervene, to promise Kaywe will address her querybut totryand resolve one issue at a

time.)

Teacher:OK so we will have to go back and check on this 'classroom) table

later, won't we. You're saying on this 'ruler] table, I've rigged the situation


28/28

28

a bit, Kay, because I got a bendy ruler. OK. We'll come back to that ...

probably today ... but let's just stay with this situation ... 'the ruler

table) may not be identical to that, but it's a situation in its own right.

Kay: Yeah.

II think thatKay trusts me to remember to return to her point.)

5. Metacognition and Conceptual Change 163

Learning Material for Concept and Conceptual Change

Documents

Transcript of Learning Material for Concept and Conceptual Change