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Instructional Science28: 199–226, 2000. © 2000Kluwer Academic Publishers. Printed in the Netherlands.

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Writing and conceptual change. What changes?

LUCIA MASON1 & PIETRO BOSCOLO2 1Department of Pedagogical, Psychological and Didactical Sciences, University of Lecce, Via Stampacchia 45, 73100 Lecce, Italy, e-mail: [email protected];2Department of Developmental and Socialization Psychology, University of Padova, Via Venezia 8, 35131 Padova, Italy, e-mail: [email protected]

Received: 30 December 1997; in final form: 7 April 1999; accepted: 24 June 1999

Abstract. This study was focused on elementary school students’ processes of scientific understanding within a classroom environment characterized as a community of discourse. In particular, it explored the role of written discourse both on the plane of knowledge devel- opment and the conceptualization and evaluation of the writing activity itself. The purposes of the study were: (a) to see whether students could use writing as a means to express and compare ideas, reason and reflect on them in the process of scientific understanding; (b) to see whether writing in the service of learning facilitated the understanding of the new topic through conceptual change; (c) to see whether writing affected the conceptualization of the writing activity itself. Thirty-six fourth graders divided in two groups, experimental (writing) and control (no-writing), were involved in the implementation of curriculum units on plants, whose target concept was photosynthesis. The findings show that in the experimental group the students reached a better conceptual understanding of the target concept and more advanced metaconceptual awareness of the changes in their own knowledge structures. Moreover, the conceptualization of the writing activity seemed to change as well to some extent as writing in a conceptual change process affected the ways learners viewed some functions of it.

Keywords: conceptual change, writing-to-learn, writing in science, writing perception

Introduction

This study is part of a wider research project on educational contexts that facilitate and support conceptual change in science domains. It tries to relate and combine the most recent research issues concerning conceptual change and writing for learning. Elementary school students’ processes of scientific understanding through conceptual change within classroom environments characterized as communities of discourse (Fish, 1980; Brown & Campione, 1994) are analyzed. In particular, the role of written discourse is inves- tigated both on the plane of knowledge development and the perception and evaluation of the writing activity itself. Recent issues on conceptual change learning in science domains and writing-to-learn are to be considered here.

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Science learning and conceptual change

Research on learning and instruction has shown that humans construct indi- vidual knowledge systems on the basis of their everyday experience. When confronted with scientific information about the physical and natural world students are not “empty vessels”. Nearly 3,000 investigations into various aspects of their conceptions (see Pfundt & Duit, 1994) testify a great deal of interest in this field of research. Often students’ personal knowledge is incom- patible with the scientific knowledge taught in school. Therefore, classroom learning requires re-organization of existing knowledge structures, that is, conceptual change learning (Carey, 1985; Driver, 1989; West & Pines, 1985). However, it has also been documented that students’ alternative conceptions are very resistant to change (e.g., Champagne et al., 1982; McCloskey, 1985) in spite of a great deal of classroom instruction aimed at teaching the scientific perspective.

The question of conceptual change has become one of the topics most investigated by cognitive and educational psychologists as well as science educators interested in the learning processes that take place during the imple- mentation of curriculum materials. Researchers have investigated different aspects of conceptual change. Theoretical and empirical studies have pointed out several aspects of this process. Particular emphasis has been placed on investigating the kind of conceptual change which occurs in the learning of scientific concepts and through what mechanisms it is achieved. Controver- sial interpretations have been proposed on these aspects that entail different educational implications (Caravita & Halldén, 1994; Carey, 1985; Chi, 1992, 1994; diSessa, 1988; Tiberghien, 1994; Vosniadou, 1994). Despite their diver- gences, researchers share a common view, that is, conceptual change is rather difficult to achieve as it entails a very sophisticated set of cognitive and meta- cognitive abilities. To bring about conceptual change some researchers have developed models, for example, Posner et al. (1982) have pointed out the characteristics necessary to scientific information in order to be integrated in learners’ conceptual structures and consequently the conditions under which conceptual change is more likely to occur. Specific curriculum materials have also been prepared to engage students in a process of knowledge restructuring (e.g. Roth, 1985). Moreover, many strategies have been suggested for facilit- ating conceptual change (e.g. Driver, 1989; Dykstra et al., 1992; Guzzetti et al., 1993; Roth et al., 1987; Smith, 1991; Smith et al., 1993).

It is interesting to note here the crucial importance of creating an authen- tic learning environment in the classroom where students can make sense of science and use science to make sense of the world. The methods and strategies used in such an environment should guide students toward a genu- ine understanding of science (Glynn & Duit, 1995). Influential research has

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highlighted that it is crucial to engage students’ interests, attitudes and beliefs; activate their existing mental models or representation systems; encourage them to pose their own questions and doubts, generate hypotheses, explore alternative solutions; stimulate them to think metacognitively, reflecting on their own and others’ ideas and beliefs. In the classroom a community of discourse (Fish, 1980; Brown & Campione, 1994) should be created, which values the practice of argumentative thinking to give students the opportunity to verbally express their conceptions and explanations, to compare, question, criticize and evaluate them. Within a community of discourse, the study reported below stresses in particular the relationship between conceptual change and writing for learning.

Writing for learning

Several studies have been conducted on the use of writing as a means of fostering learning and thinking. Langer and Applebee (1987), in their seminal study on writing-to-learn, argued that writing on a topic allows the writer to clarify his or her knowledge, organize the ideas to be written, and reflect on the learning experience.

In recent years the role of writing in scientific literacy, and particularly in conceptual change learning, has been stressed in several studies (Ackerman, 1993; Glynn & Muth, 1994; Fellows, 1994; Keys, 1994; Mason, 1998), where writing is mainly conceived and used as a recording tool (Boscolo, 1995). Subjects are requested to write about their beliefs on a topic, the way(s) their beliefs changed, what they understood about an experiment, and so on. There- fore, writing has two functions, one from the point of view of the subject, the other from the experimenter’s point of view. On the one hand, a subject can express and clarify his or her ideas, while on the other, the experimenter can analyze several aspects of conceptual change through writing.

Rivard (1994; Rivard & Straw, 1996) argued that studies on this topic are not always well designed and clearly reported. Particularly, he pointed out that the role of writing in effecting conceptual change has not received enough attention and more studies are needed on how students’ conceptual frameworks are transformed by different types of writing tasks. He also sug- gested using writing tasks that require students to reflect upon the differences between their own conceptions and correct ones.

Few, if any, scholars seem to assign to writing the function which Bereiter (1980) called epistemic, i.e., when a writer uses what he or she has written as a tool for reflection. According to this view, a writer’s thoughts are clarified by writing and, by reflecting on writing, the writer is forced to make his or her thoughts more precise. Thus, thinking and writing interact in that writing

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is not only a mirror or “window” for thinking, but thinking is, reciprocally, influenced by writing. The use of writing as a “thoughtful” activity is an important aspect of intentional learning (Bereiter, 1990, 1994; Bereiter & Scardamalia, 1989). Intentional learning has knowledge as its goal, and writ- ing is conceived as a tool for stimulating and fostering children’s ability to organize their knowledge and reflect upon their own beliefs.

Of course, to make elementary school students view writing as an epi- stemic activity is an aim which is too ambitious, if not unrealistic. However, we think that it is possible to create the conditions for building different ideas about writing, and one of them could be a classroom learning context where students are deeply involved in making sense of new concepts and writing is used as an effective tool for thinking and reasoning in the process of developing understanding.

The main purpose of this study was to help elementary school children view writing in a science class not only as a way of recording events and activ- ities, but also as a meaningful activity, i.e., as a way of expressing ideas in order to reflect, reason and compare. Such uses of writing could lead students to a better conceptual understanding of the new scientific topic. Moreover, the use of writing in the service of learning could modify children’s beliefs on the functions of writing, which in elementary school is generally used in “canonical tasks” (essays, summaries, reports, free and personal texts). Our assumption was that giving children the opportunity to experience different writing functions would help them both to construct new knowledge, which requires conceptual change, and conceptualize writing in a different way. If this assumption is right, beside the fact that writing for learning may be effec- tive in sustaining a process of knowledge restructuring, a change in children’s attitudes toward writing could be expected, more specifically those changes described as follows.

1. Using writing in a meaningful context may make writing more attractive to children.

2. Children’s perceptions of the differences between oral and written expression in the classroom may change. Usually children view cer- tain school tasks as typically oral (e.g. answering teachers’ questions, discussing, reflecting, displaying learned material) and others as typic- ally written (e.g. summaries, reports, essays). Using writing as a way of expressing and investigating ideas, and reflecting on a scientific problem could change children’s perceptions of this distinction.

3. A third change may regard the perceived usefulness of the different forms of writing to learning to write. In their school experience children learn to attribute different degrees of importance to the text types they prac- tice. Some are more, others are less valued, probably on the basis of the

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frequency with which the different writing tasks are performed and the teachers’ evaluations of those tasks.

Research questions

Relating crucial issues of the most recent research on conceptual change and writing for learning, five research questions are asked in the present study: 1. Can fourth graders use writing to express ideas, reason and reflect on

them, and communicate their developing understanding? 2. Does writing in the science class improve understanding of the new topic

which implies conceptual change? 3. Does writing in the science class improve metaconceptual awareness of

the changes occurring in one’s own conceptual structures? 4. Does writing in the science class affect the conceptualization of the writ-

ing activity itself? In other words, does writing as a tool of learning in a conceptual change process also contribute to: (a) increasing children’s interest in the specific writing activities carried out in the process of scientific understanding; (b) changing their ways of categorizing school activities, i.e., the distinction between oral and written work in the science class; (c) changing their perception of the uselfuness of the specific writing activities performed in the science class?

Method

Participants. Thirty-six fourth graders (20 girls and 16 boys) attending two public elementary schools in the Padova area (Northern Italy) were involved in the study. They shared a homogeneous middle class social background. The experimental group was a class of 16 students in which the writing activity in the service of learning took place in science education classes. A class of 22 students in a different school comprised the control group who did not undertake the writing activity but did all other activities. Two students from the control group were dropped from the sample: one because of severe learning disabilities, the other because of frequent non-attendance at school because of illness. The control group was therefore made up of 20 students.

Classroom context. The class teachers were two very experienced and moti- vated science teachers. We are aware of the fact that having two groups of students taught by two different teachers may be seen as a weakness in this study. However, given the constraints of the school organization and the need

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to work with teachers who were very motivated to cooperate, we have done our best to keep this variable, that could be a source of variation in the results, under control.

It should be said that the two teachers had been working for many years in the same grade in two different elementary schools of the same district. For years they have been used to planning their shared classroom activities collaboratively at monthly meetings. These activities included establishing purposes, contents, methods, tools, and material for each curriculum unit. Moreover, they have been used to meeting in order to evaluate what had been done in the classroom and to identify what had, or had not, worked in implementing the curriculum units. They were aware of the importance of the classroom learning environment in motivating and supporting stu- dents’ construction of their own knowledge. They were very concerned with promoting in the classrooms true dialogue between the students them- selves and between teachers and students. They have been used to engaging them in group discussions in order to facilitate and sustain meaningful learning.

Since the beginning of the collaboration with the researchers (the authors) and throughout the instructional intervention the teachers have met weekly, and always in the presence of the first author. This was to plan each science class activity to be carried out in the same way, and in particular what, how much, and through what procedures they had to “teach” the students. The first author was in the classroom as a participating observer in each session devoted to the curriculum units. She could check that these were carried out in exactly the same way, the only exception being the writing activity, and that the same kind of interpersonal relations between the students themselves and between the teacher and students characterized classroom life.

In both groups all children were involved in the same observations and experiments as well as in lively discussions about the same knowledge prob- lems. In both conditions, writing and no-writing, large-group discussions (the whole class) took place in almost every weekly session devoted to implement- ing the curriculum units, which took about two and a half months. In addition, the same cards, prepared collaboratively by the teachers at the meetings in the presence of the first author, were used in both groups to synthesize the newly learned concepts.

We can say that the teachers overall applied a controlled method and the differences observed between the two groups are not due to a better teaching performance by the teacher of the experimental group or a worse performance by the control group teacher. Obviously, we cannot maintain that two teachers are the same as one, but that their classroom behavior was very similar and the

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same when considering how the instructional intervention was implemented, with the exception of the use of writing.

Only in the experimental condition was writing for learning carried out individually at certain points in the curriculum units implemented with dif- ferent aims. It is worth noting that the experimental group teacher had never used writing to assist learning in the science class, but had been trained to do it. She introduced the different functions of writing in the science class both by giving instructions on how to use writing and “modeling”, i.e., showing the children its various aims. In particular, the following procedure was adopted by the teacher.

a. From the beginning of the scientific activity she made the children aware that notetaking, commenting on, reasoning and reflecting upon ideas, expressing doubts, synthesizing what one has learned, could be writing activities.

b. At the end of the first session the children were invited to write about the scientific activity which had impressed them most. The teacher “modeled” the writing behavior by taking notes with children and show- ing the use of notes (recording, reflecting, expressing, etc.). The children were invited not to worry about the errors they made in writing. If they felt unable to express a thought or comment, the teacher would help them clarify their ideas.

c. At the beginning of each session the teacher and children used what they had written as a link with the previous session. The teacher invited chil- dren to gather ideas by reading their notes, which were considered as a personal way of reasoning and reflecting on a scientific problem, and a useful way of recording and communicating one’s own ideas.

Subject matter. Three curriculum units on plants were implemented. The third and target unit was on photosynthesis. The two previous ones dealt with the parts and functions of plants and plant respiration.

Tasks and scoring. In both groups conceptual understanding of the target topic was assessed by three tasks.

(a) Pre- (to identify the students’ prior knowledge) and post-instruction ques- tionnaires with 19 open-ended questions on plant nutrition and growth (e.g. “What do plants need to stay alive?”; “What is food for plants?”; “Where does a seed get nutrients to grow?”; “Why are leaves green?”; “What is the main difference between plants and animals?”; “Could animals live in a world without plants? Why?”; “Why are the parks of a city called ‘green lungs’?”). The answers to each question were scored on the basis on their correctness and completeness. For example, the answers

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to the question “Could animals live in a world without plants?” “Why?” received 1 point for “no” and 0 points for “yes” answers. Moreover, the justification “Because herbivorous animals would die” was given 1 point while the justification “Because all animals need oxygen produced by plants” was given 2 points.

(b) Post-instruction transfer questions (e.g. “Is a mushroom a plant?” “Why?”; “What would happen if there were fifty percent less sunlight per day?”) requiring application of the newly learned concept of photo- synthesis. In this case too, the answers were scored on the basis of their correctness and completeness. For example 1 point was given for “no” and 0 points for “yes” answers to the first question. Moreover, the justifi- cation “Because it is does not have chlorophyll” was given 1 point, while the justification “Because it is not a producer, it cannot photosynthesize” was given 2 points.

(c) Three short post-instruction texts on plant nutrition, respiration and kinds of sap flowing in plants. They were scored by giving 1 or 2 points for each item of correct information. For example in the text on plant nutrition, 2 points were given for stating that photosynthesis is the process of food production which transforms raw material and that plants are the only living beings able to manufacture their own food (producers) instead of taking it from the environment. 1 point was given for respectively men- tioning, by explaining the process, light, chlorophyll which captures light, water and carbon dioxide as raw substances, the production of carbo- hydrates, the production of oxygen, that sap contains sugar and flows from the leaves to the non green parts of a plant. The maximum score was 10 points. An additive score was calculated for all three short texts for each student.

Moreover, five post-instruction questions were asked to ascertain the stu- dents’ metaconceptual awareness: “Do you think your ideas on plant food have changed?” If so, “What were your initial ideas?”; “Why did you have those ideas?”; “What are your current ideas?”; “Has changing your previous ideas been easy or difficult and what made it easy or difficult for you”. The “yes” answers scored 0 points when a student was not able to express any metaconceptual awareness while 1 point was given for mentioning each of the following aspects: initial ideas, why they had been changed, current ideas, the production of sugar as an energy-containing food as the main idea, how they managed to change previous ideas.

All scores were attributed separately by two independent judges. Agree- ment was very high (97%) and disagreements which only concerned the students’ metaconceptual awareness were resolved by discussion in the presence of the authors.

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A qualitative analysis was also carried out on the experimental group chil- dren’s texts. In order to emphasize changes in writing, the analysis focused on each experimental group participant’s texts written at the beginning (November–December 1996) and at the end of the intervention (February 1997) to see any change that could reasonably be ascribed to the “new” way of using writing: i.e. the transition from list-like to “personal” writing, and from narration to argumentation. The analysis was carried out separ- ately by the two independent judges. Their agreement was again very high (95%). Disagreements were resolved by discussion in the presence of the authors.

The effects of the science class writing activity on the conceptualization and evaluation of the activity itself was assessed in both groups in three ways. (a) Pre- and post-instruction “Do you like” questionnaire on how much

they liked 25 different activities (e.g. “Drawing”, “Doing experiments”; “Studying the science textbook”) – among them different forms of writ- ing carried out in the science classes by the experimental group (e.g. “Writing on what has been discussed in the group”; “Writing reflections on the new things you are learning”) – to be rated on a 5-point Likert-type scale (1 = Not at all, 5 = Very much).

(b) Pre- and post-instruction questionnaire with 14 statements for the attribu- tion of several school activities, some of them crucial to the science class (e.g. “to discuss a topic”; “to reason and reflect on the new things you are learning”; “to report on a classroom discussion”), to the oral or written “category” to be rated on a 5-point Likert-type scale (1 = only oral, 5 = only written).

(c) Pre- and post-instruction task which asked the subjects as the follow- ing. “Imagine you are in a country where elementary school children can do some things (research, group work, arithmetic problems, science, history, etc.), but cannot write texts. If you had to help these children learn to write texts, which text types among those listed below would you consider most adequate, and why? Which would you not choose?” Each subject was given a list of 14 different writing types, including those carried out in the science class by the experimental group (e.g. “To write a report on a classroom discussion”; “To write reflections on the new things you are learning; “To write reflections on experiments”; “To write on what you are not able to understand”). Such a task allowed verification of whether the experimental group would value the specific types of writing done in the science class more and recognize them as useful for learning to write texts.

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Results

Prior knowledge

First of all it is important to point out that a two-tailedt test revealed no signi- ficant differences between the experimental (writing) and control (no-writing) group in the pre-instruction questionnaire on plant nutrition and growth, as evidenced by a mean score of 13.87 (SD = 3.46) for the class which made up the writing group and 12.95 (SD = 4.33) for the control group class. In both groups the teachers had not yet introduced the concept of photosynthesis, but in previous school years the children had performed some experiments in the classroom to investigate the effects of the presence or absence of water and light on seed germination and plant growth. In both groups the students held the same alternative conceptions on plant nutrition identified by previous investigations on the topic of photosynthesis (e.g., Haslam & Treagust, 1987; Leach et al., 1996; Mason, 1994; Mintzes et al., 1991; Smith & Anderson, 1984; Stavy et al., 1987; Wandersee, 1983; Wood-Robinson, 1991) defined as “the most important biochemical process on earth” (Arnon, 1982). We briefly report here some of the most interesting and challenging prior con- ceptions held by the students of both groups to illustrate the initial conceptual scenario.

The function of leaves. In identifying the main parts of a plant most children mentioned the leaves. Obviously, none of them referred to their function in the food production process. The most common statements were: “Leaves are to form the foliage of a plant”; “Leaves are for beauty”; “Leaves are to absorb water” (directly from the rain); “Leaves are to receive sunlight”; “Leaves are to make a tree colorful”.

The green color of leaves. None of the children referred to the presence of chlorophyll in leaves. The most common answers were: “The plant keeps the leaves green”; “It is by nature”; “Because the light makes them green”; “Because they are evergreen”.

The plant’s needs. Almost all children mentioned soil, water, sunlight and warmth as necessary elements for a plant to stay alive. Very few added air and people’s love.

The plant’s food. All children in both groups identified water and minerals as food for plants. Some added soil and fertilizers given by people.

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Where a seed gets its nutrients. As expected, none of the children referred to the energy store inside a seed but most said that the nutrition of a seed came from the soil. A number added water as a source of food.

The main difference between plants and animals. As expected, none of the children referred to producers and consumers but mainly pointed out that animals move and plants do not (22 out of 36). Other recognized differences were: “Animals have a skeleton, plants do not; “Plants eat water and soil, instead animals are herbivores and carnivores”; “Animals take in oxygen whereas plants release it”. This last idea, very common among the students of both groups as evidenced by classroom discussions, revealed the widespread confusion between photosynthesis (although they did not name the process, just the release of oxygen) and respiration in plants. All students initially believed that plants breathed in the same way as humans only at night, since during the day the process was reversed.

Animals in a world without plants. All children in both groups stated that animals could not live in a world without plants. Their justifications referred to the fact that plants release oxygen which is indispensable to all animals (16 out of 36) and the fact that herbivorous animals would soon die (18 out of 36). As pointed out above, the students who maintained that oxygen came from plants did not relate oxygen release to the carbohydrate production process but believed that plants breathe in a reverse way compared with humans.

The parks of a city as “green lungs”.The most common idea (14 out of 36) was apparently the correct one: “Because there are many plants which give oxygen”. Once again, as noted above, the students believed plants breathe in a reverse way. Other much less common ideas were not related to oxygen production: “Because there is plenty of grass and trees”; “Because it is their natural environment”.

The conceptual change required. All the researchers who have studied chil- dren’s ideas about plants nutrition have highlighted the difficulty that the topic poses to the learner, and the crucial importance of a meaningful understanding of such a topic to the elaboration of an integrated view of the cycle of matter and flow of energy in ecosystems (Eisen & Stavy, 1991). The construction of the essential concept of photosynthesis requires that the children revise their strong initial beliefs by changing their representation about “food” as material that all living organisms take in from the environment, so water and minerals, and in some cases also soil, air and light were considered food for plants. Viewing a plant as an entity capable of manufacturing its own food instead of taking it in from the outside implied a change in the dis-

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tinction between animals and plants. In Chi’s (1992; Chi et al., 1994) terms, the conceptual change requires a changewithin an ontological category, the “Matter” tree, in particular a changeacrossparallel categories, “animals” and “plants”,within the ontological “Matter” tree, one of the major ontological trees. In Vosniadou’s terms (1994), the change at the level of the specific theory, that is a plant does not live on water to energize itself but produces its own nutrients, implies a change at the level of the framework theory, that is, in the ontological distinction between animals and plants.

Toward the construction of new knowledge: talking and writing for scientific understanding

In both groups almost all class dialogue was a true dialogue between the students themselves and between the teacher and students. Crucial importance was attributed to the learners’ expression, comparison, questioning and critical evaluation of their own conceptions through the systematic use of collaborative discourse-reasoning in classroom discussions on knowledge problems. To give an example of the argumentative talk which developed between the teacher and learners, two excerpts1 from the first large-group discussion on what food for plants is, which took place in both classrooms, are introduced here. The first excerpt comes from the experimental group, the second from the control group.

Teacher: You’ve said that a plant consumes water. You’ve already written it at the beginning. Now you know that a plant has to carry on many activities also, so I’m asking you “is it possible that water’s enough?”. Think of this question. Can an animal live on water only?

Many: No, surely not. Teacher: Now say, explain why you think that for a plant water’s enough.

Elena: Because for the plant water’s to drink, it’s got water to drink. Alessia: Yes, ok, but the light? Elena: A plant doesn’t eat it!

Silvia 1: We’re talking about food. Elena: Yes, water’s to drink and mineral salts are to eat. When they’re in

the leaves’ veins, it can eat them. Giulia: I want to answer the question. Also for me water’s enough, that is,

the plant isn’t able to eat anything else as it can’t eat solid things, absorb them. How could it do this? It can’t, instead it can absorb liquid things and mineral salts through root hair.

Teacher: And is water enough? Giorgia: Uhm . . .

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Rita: I believe that water contains many other elements, substances as food for plants. We call it water in general but if we begin to list all the things contained in water we take a long time. Moreover, there are carnivorous plants which eat small insects, there are also those.

Teacher: When we go to visit the botanical garden, we’ll see the carnivorous plants so fascinating for you.

Ilaria : No, I believe that water isn’t enough. If we make a comparison . . . some time ago we said that the plant’s a living being, we’re also living beings. I’m making a comparison with men and women, we can’t live on water only, it’s not enough for us, we need many more things. Moreover, as Alessia’s said before, the plant also eats light. The light crosses it, I mean.

Alessia: I’m able to explain it. The light filters through the plant and warms it. In winter when it’s always cold, plants, like those which belonged to my neighbor, died because of the cold. I believe the light’s as indispensable as water. With water and mineral salts a plant eats but with the light it gets warm.

In this sequence we can see children who, on the basis of their experience of growing plants, held the strong belief that food for plants was water only, conceived by some as containing nutrients. Other children, on the basis of the analogy with animals’ food needs, maintained that water could not be enough. In trying to understand what besides water could be food, Alessia tried to make a connection between food and the light which makes a difference in plant growth. The teachers’ interventions are noteworthy for their scaffolding role. Without giving mere information, cognitively relevant questions were asked to call the children’s attention to the crucial aspects of the specific knowledge problem.

Teacher: Well, is food for plants only water with mineral salts as you’ve just said? Are water and mineral salts enough for the plant to do all the things it has to do?

Dario: No, also air, oxygen and carbon dioxide to breathe. Teacher: We’re talking about plant’s food at the moment. Nicolò: Yes, water but also light. Andrea: But the light isn’t useful to eat, the light lights. Alessio: It makes plants grow. Marco: We’ve done an experiment. The plant in the dark inside a cup-

board turned yellow and it almost died, whereas the plant on the window-sill was in good condition, alive. Then we changed

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places and moved the plant which had stayed in the dark into the light and it recovered very well.

Alessandro: But the light isn’t food, the plant can’t eat it. Alessio: I believe that the light’s useful for a plant to grow, but not to eat. Nicolò: Also air’s important to a plant.

Teacher: Plants are living beings like animals are, you’ve said that before. Think of this: “Can an animal live on water only?”

Many: No, no. Teacher: Does water give energy?

Some: Yes. Diego: If you’re thirsty, water. . . you.

Michele: Yes . . . try going on a water diet and then you’ll see. . . !

In this sequence we can see the children’s effort to think of something else beside water as food for plants, that is light and air, easily recognized as important to grow but not to eat. The quality of the teacher interventions are also remarkable in this excerpt as they are mainly aimed at posing questions to lead the students to reason on the crucial aspects of the specific knowledge problem.

The only variable which differentiated the experimental from the control group was the use of writing to assist learning. The written production showed that the students in the experimental group were able to use writing for the different means which had been illustrated to them. More specifically, there were the following functions of children’s writing: − to express doubts, reflections and surprise about teacher’s explanations

and the results of experiments; − to hypothesize and predict the results of an experiment; − to argue about scientific questions (e.g. “is a mushroom a plant?”); − to summarize what they learned from teacher’s explanations and experi-

ments. − to compare and reflect on old ideas and new explanations about scientific

phenomena. Some examples of short texts written by the students within the curriculum

units on respiration and photosynthesis are reported here as evidence of their use of writing in the service of learning. The first text documents the concep- tual difficulties experienced by a child engaged in understanding how oxygen is created by plants. The child made what was puzzling her explicit.

I am not able to understand how oxygen is created. I think it comes from trees but I cannot find in my mind an explanation of how it happens, that is, I cannot figure out how a tree gives out oxygen and, at the same time, keeps a little for itself to live on. For example, my questions are:

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The smallest plants, how do they get oxygen? Are they like trees? And in what way do they also breathe oxygen for themselves? I am not able to find an answer to these questions; in short I have not yet understood how oxygen is created. (Gloria)

The next three examples of texts deal with the problem of food for plants. The learners wrote their ideas after the first classroom discussion (an excerpt is reported above) on the crucial question. Their written reflections illustrate how they could reason on their own and the ideas of others. On the basis of her experience, the first child expressed her strong belief that water was the only food. Reasoning by analogy, the second child doubted that water was everything for plants. The third child thinking that water was not enough, hypothesized that plants have a “special substance” from birth to death.

My idea is that a plant eats water only because the plants I have at home take in water and nothing else. There are many new leaves on one and the other has got fat. When these plants were in my grandmother’s house they were almost dead but now in my home they are alive with new leaves. Animals cannot eat only water because they have more appetite and are like people. I feel I am very sure that plants eat water only. (Jessica)

Can plants stay alive only through water? This is the question. In my opinion they cannot live on water only because they also need sunlight and should be put outdoors. Yes, it is true that water contains many mineral salts but my idea is that plants need sunlight as it warms them and if they lived in the cold they would die. Jessica has said that she keeps a plant inside always. I think it is impossible for a plant to stay alive if it is always inside as it needs to stay in the air and capture sunlight not the artificial light of a room. All one of my neighbors’ plants died because they did not have the true, natural, sunlight. I made a comparison with cactus. The cactus is a plant which lives in the desert. Yes, I think it needs water but above all warmth and sunlight; it is in the desert, in fact. Moreover, I have made another comparison: Can a human being survive only on water and stay in the artificial light of lamps? No, I do not think so as humans need other food and to breathe fresh air. My conclusion is that plants need many things just like humans. So far I am not able to say what these things are. (Alessia)

For many of my classmates water and mineral salts are food for plants. On the other hand my idea is that water and mineral salts like calcium, magnesium, sodium, potassium, sulphur, etc., are not enough

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because I think that when the plant takes water to the leaves, a special substance produced from birth is put in it. Such a substance is useful both to the leaves and the stem. When this substance is used up, the plant dies. Moreover, my idea is that also sunlight is like a “nutrient” for the plant. I had my own plant, a small plant, and I used to give it water but I kept it in the dark and unfortunately after a week it dried up and died. (Giulia)

The next two texts on the changes which occurred in one’s own concep- tual structures are examples of metaconceptual awareness expressed by two children who experienced a successful revision of prior conceptions while making sense of the scientific concepts.

I believed that leaves are green because God had created them green but I have understood that they are green because they contain chlorophyll. I believed that plants breathed only in the night: now I know that they always take oxygen in and give carbon dioxide out. At the beginning I thought that “photosynthesis” was the name of a new plant but then I understood that it is the mechanism by which the plant manufactures its own food without being helped by anybody else. Moreover, I believed that without sunlight a plant could grow the same but now I am convinced that without solar energy it dies since it cannot be a producer. Before this work I did not know that root hairs are special hairs which absorb water for the production of food. (Silvia)

I have understood everything that has been said here but I cannot imagine it. Before I believed that plants consume water and mineral salts but now I have figured out it is not that. Plants use water to prepare glucose and starch, but not only water, also carbon dioxide is necessary. Now I also know that trees keep stored food for winter and periods of drought. I believed that water was everything for a plant, whereas it is only a raw material that does not give energy. I knew that oxygen came from plants but the concept that oxygen is a by product of photosynthesis was not in my mind. The plant is a producer while we are consumers but it breathes oxygen twenty-four hours a day like us. (Rita)

The last text introduced here is an example of a report written after a classroom discussion by the only child who strongly expressed her idea that a mushroom is a plant. Interestingly, she finally referred to the sophisticated epistemological belief that not everything written in a textbook is necessarily true in order to support her alternative conception.

We had a very lively discussion. My first idea was that a mushroom is a plant whereas all my classmates said that it is not. I believe it is a plant

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Table 1. Means and standard deviations in pre- and post-instruction open-ended questionnaire

Group Pre-instruction questionnaire Post-instruction questionnaire

M SD M SD

Experimental 13.87 3.46 30.62 8.51

Control 12.95 4.33 22.65 7.88

p < 0.001.

Table 2. Means and standard deviations in post-instruction transfer questions, short texts, and metaconceptual awareness

Group Transfer questions∗∗∗ Short texts∗∗ Metaconceptual awareness∗

M SD M SD M SD

Experimental 3.37 1.02 9.50 3.09 3.50 1.15

Control 2.05 1.46 6.25 3.44 2.45 1.63

∗p < 0.05;∗∗p < 0.01;∗∗∗p < 0.005.

because although it is red it can be a plant since there are red trees, like the red acer, that are plants. My classmates maintain that a mushroom is not a plant as it cannot produce its own food by itself. At home I reflected on this and I came to the conclusion that maybe it cannot be a plant because it does not have any seeds. However, I am still not sure that it does not have any seeds. Now I believe even more that a mushroom is a plant because Giulia has brought a book to school in which it is written that a mushroom does not contain chlorophyll. As my teacher has said many times, even in books there can be mistakes! (Ilaria ).

Conceptual understanding

Open-ended questions. As an effect of the instructional intervention aimed at stimulating and supporting conceptual change learning, the students’ con- structed new knowledge by revising their prior conceptions. An ANOVA for repeated measures indicated that both experimental and control groups improved their conceptual understanding as measured by the questionnaire with open-ended questions:F (1, 34) = 218.04,p < 0.001. The ANOVA also showed a significant “group× time” interaction. Indeed the experimental group reached a higher level on the post-instruction questionnaire,F (1, 34) = 14.04,p = 0.001 (see Table 1).

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Transfer questions. A one-way ANOVA showed a significant difference between the experimental and control groups on the transfer questions requir- ing application of the newly learned concept of photosynthesis: the former outperformed the latter:F (1, 34) = 9.35,p < 0.005 (see Table 2).

Short texts. A one-way ANOVA also showed a higher conceptual understand- ing among the students of the experimental group in the short texts on plant nutrition, respiration and sap flowing in plants:F (1, 34) = 8.63,p < 0.01 (see Table 2).

Metaconceptual awareness.Concerning the students’ awareness of the changes which occurred in their conceptual structures, a one-way ANOVA showed significant differences between the two groups,F (1, 34) = 4.69,p < 0.05. In particular, it could be seen that only among students in the control group were there the lowest levels and only one of the highest levels. Here three high-level metaconceptual reflections are reported to illustrate how the children expressed self-regulated learning (see Table 2).

Even at the beginning I knew that plants ate but I believed that their food was water only and it gave them all they needed, but water does not give energy. Now I have changed my idea as I have understood that plants are the only living being producers. I have to say that the change has not been very easy but thanks to my classmates and the teacher I have managed to change my ideas. (Giorgia, experimental group)

I believed that plants were living beings. For me the word “food” meant bread, pasta, cookies, etc, so I believed that plants did not eat. I had that idea because I had never seen a plant eating bread, pasta or something like that. Now I have figured out that also plants eat and that they are the only living beings able to prepare their own food instead of taking it in already done. I changed my idea through discussions and experiments, but it has been difficult because my idea was very strong. (Alessia, experimental group)

Before I believed that plants only eat things taken from the soil: water and mineral salts. I believed that because I knew that plants had roots underground, so they could take in food from the soil only. Now I know that plants take water from the soil but they also make their own food (sugar). The mechanism of sugar production by plants has been explained. It has been pretty easy to change my ideas as I have read the cards. (Michela, control group)

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Written texts qualitative analysis

Although the present study was aimed at analyzing the effects of the instruc- tional intervention on children’s conceptions of writing, the frequent writing tasks during science class activities might have produced some effects on children’s writing competence. Unlike many instructional interventions in which is used to assess student learning, in the present study writing has been conceived as an activity closely connected to science learning. The experimental group children used writing during and immediately after the scientific activities in which they were involved. Therefore, not only did chil- dren learned new concepts about plants but they also approached new uses of writing. In other words, they were introduced to a new genre: writing about science learning.

The qualitative analysis focused of two text features whose changes from the beginning to the end of the intervention could reasonably be ascribed to the “new” way of using writing, i.e., the transition from list-like to “personal” writing, and from narration to argumentation. As matter of fact, these two features are closely linked in young children’s writing.

When required to write a report of a scientific activity elementary school children often adopt a “narrative” stance: e.g. they write a list of what happened during a classroom discussion or experiment, of what they learned or did not understand, etc. This way of using writing is usually impersonal, in that the writer tells “objectively” what happened in his/her classroom, without expressing any personal reflections or doubts. This strategy is similar to Bereiter & Scardamalia’s (1987) knowledge-telling, in that the writer’s main concern is with expressing what he/she remembers of an activity or event, with no transformation of topic knowledge. Instead, an expert writer elaborates his/her topic knowledge according to a writing plan. The main features of texts written according to the list-telling strategy are chronological order, the use of very simple cohesion links (then . . . , then . . . , then . . . ), a detailed list of “what has been done”, and the lack of a writer’s point of view about his/her experience, even if a very simple one.

Here are two examples of list-like reports written in the two first weeks of the instructional intervention. The first regards a classroom discussion, the second an experiment.

Today we talked about plants, how a plant lives, everyone said some- thing, for example that plants live on air and oxygen and water especially from the ground. After we talked about how oxygen enters the plant for example some people said that it comes from the leaves and others from the trees, and after we said other things, that for us the plant’s heart is in the trunk and at the end we wrote this text. (Jessica, 11 November 1996)

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Today we talked about transpiration of the leaves and where the little droplets on green leaves come from. Giulia said that the brown leaves are dry and the green leaves will also become dry. Gaia asked a question: “What do plants eat?”. Rita said that they eat only water and Gaia: “Only water?”. Then we tasted the leaves a bit. Then we made some observa- tions. My friend Giulia made a comparison: that the green leaves die after and the brown ones before. (Alessandro, 23 November 1996)

Here are the same children’s written texts at the end of the instructional intervention.

Last Saturday we talked about mushrooms and my school-mates and I said that they are not plants, instead one of my class-mates said that it is a plant because they live on trees. But this reason is not enough to say that a mushroom is a plant. I think that a mushroom is not a plant because it cannot feed itself and to make sugar and it does not produce oxygen. (Jessica, 12 February 1997)

This experiment was carried out with two transparent containers, two green plants and two candles. A candle was put under a container and the other under the other container with the plant. The result: the candle under the container with the plants went out first, because the plants had consumed the oxygen by breathing both day and night. In this way I was able to understand that the leaves were making, that is emitting, little oxygen because they consume it. (Alessandro, 8 February 1997).

Although these texts can by no means be considered examples of know- ledge transforming strategy, a different way of using knowledge emerges. In Jessica’s text, after the setting (“Last Saturday”), the two opposing positions about mushrooms are presented, she argues to support her own. Alessandro’s text is also very concise, but no essential information is omitted. In fact, there is a description of the experiment and its effect on Alessandro’s understanding of the phenomenon.

The transition from a “narrative” to a more “argumentative” way of writing was apparent in 13 out of 16 children’s texts.

Writing and interest in writing in the science class

“Do you like” questionnaire. An ANOVA for repeated measures was per- formed for each writing task submitted to rating. Only a tendency to signi- ficance (p > 0.10) was found for the interaction group× time regarding one of the writing tasks carried out in the science class, that is, “Writing on what has been discussed in group”. At the end of the instructional intervention,

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Table 3. Means and standard deviations in pre- and post-instruction oral/written ratings

Group Pre-instruction Post-instruction

“To reason and reflect on a phenomenon”∗

Experimental 2.43 1.03 2.93 1.06

Control 2.40 1.04 2.80 1.28

“To reason and reflect on new things you are learning”∗

Experimental 2.31 0.94 2.87 0.95

Control 3.05 1.09 2.40 1.18

“To express what you are not able to understand”∗∗

Experimental 2.00 1.09 2.31 1.19

Control 2.90 1.48 1.90 1.11

∗p < 0.05;∗∗p < 0.01

the experimental group children tended to rate more highly such a form of writing than the control group, that is, only the subjects who used writing also for recording, making comments and reasoning on what had been discussed in the classroom were more likely to increase their interest in this type of writing.

Attribution of science class activities to oral and written “category”

Oral/written ratings. An ANOVA for repeated measures was performed for each activity submitted to rating. Significant effects and interactions were found for the following activities which were also performed in written form by the experimental group (see Table 3). − “To reason and reflect on a phenomenon”, time variable,F (1, 34) =

4.64, p < 0.05. At the end of the science activities, both groups rated this activity as more “written” than at the beginning.

− “To reason and reflect on new things you are learning”, “group× time” interaction,F (1, 34) = 5.39,p < 0.05. While at the beginning of the science activities, the experimental group rated this activity as mostly oral and at the end as both oral and written, the control group decreased their rating showing they perceived the activity as mostly oral at the end of the instructional intervention.

− “To express what you are not able to understand”, “group× time inter- action”, F (1, 34) = 8.21,p < 0.01. The same change of perception in

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Table 4. Number of students who chose either as useful (yes) or not useful (no) the writing activities carried out in the science class before and after instruction (McNemar test)

Group “To write reflections on new things “To write reflections on

you are learning”∗∗ experiments”∗∗∗

Experimental Post-instruction Post-instruction

no yes no yes

Pre-instruction no 0 11 Pre-instruction no 2 9

yes 1 4 yes 0 5

Control Post-instruction Post-instruction

no yes no yes

Pre-instruction no 3 3 Pre-instruction no 0 3

yes 3 11 yes 5 12

“To write reflections on what you are “To write a report on a classroom

not able to understand”∗ discussion”∗∗ Experimental Post-instruction Post-instruction

no yes no yes

Pre-instruction no 3 10 Pre-instruction no 1 8

yes 1 2 yes 0 7

Control Post-instruction Post-instruction

no yes no yes

Pre-instruction no 7 3 Pre-instruction no 4 4

yes 4 6 yes 2 10

∗p < 0.05, two-tailed. ∗∗p < 0.01, two-tailed. ∗∗∗p < 0.005, two-tailed.

the two groups also emerged for this activity, in that at the end of the science activities the experimental group rated it less “oral” than at the beginning, whereas the control group rated it more “oral”.

In sum, after the science education experience, the experimental group children perceived two crucial activities carried out in the class, that is reflecting and expressing doubts, as activities which could also be performed through writing and not mainly orally as the control group did.

Perception of the usefulness of writing in the science class

Choice/rejection of different types of writing. A McNemar test was performed for each group to see whether at the end of the science education experience

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more subjects chose some specific types of writing. Concerning the experi- mental group only, the test revealed significant differences for the four crucial types of texts carried out in the science class. At the end of the science activ- ities more children who experienced different forms of writing for learning science concepts chose these forms of writing. In other words, they found such writing tasks as useful in teaching to write texts. No differences emerged for the control group (see Table 4).

Discussion

The first research question was to see whether fourth graders could use writing-to-learn as a tool to express and compare ideas, reflect and reason on them in the process of scientific understanding. The findings indicate that writing allowed the experimental group children to express their current con- ceptions about scientific phenomena in a form they could look at and think about. Writing acted as a means of reflecting on their previous ideas and experiencing the new conceptions they were led to understand by changing their former ideas. Moreover, through writing the learners could also experi- ence what they were puzzling over when trying to make sense of developing knowledge.

The second research question asked whether the use of writing in the service of learning improved understanding of the new topic which implied conceptual change. The data indicate that it contributed significantly to a better understanding of the photosynthesis topic as the experimental group reached a higher level on all three measures: the post-instruction open-ended questionnaire, transfer questions and short texts. These findings support pre- vious research studies on the effectiveness of writing as a learning strategy (e.g. Fellows, 1994; Langer & Applebee, 1987; Keys, 1994; Rivard, 1994).

The third research question was to see whether writing-to-learn in the science class improved students’ metaconceptual awareness of the changes which occurred in their own conceptual structures. The findings indicate that writing also contributed significantly to creating or refining students’ awareness of their initial and current conceptions as the experimental group expressed a higher level of metaconceptual awareness of the path of know- ledge they had passed through in the collaborative learning context. These data provide empirical evidence that students’ metaconceptual awareness is important in the process of conceptual change (Vosniadou, 1994).

The experimental group children’s written texts qualitative analysis indi- cate that in most of them there was a transition from a “narrative” to a more “argumentative” way of writing. While using writing as a tool for learning science the children could also learn a different way of using knowledge. If

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writing helped them to better understand the new topic and to refine their metaconceptual awareness of the changes occured in their own conceptual structures, this is to be related to the quality of what has been written.

The four research question regarded if, and how, writing in the science class affected the children’s conceptualization of writing itself. We hypothes- ized that engaging learners in several writing activities related to conceptual change would produce a change in: (a) their interest in writing those specific text types; (b) their categorization of science-related activities, based on the traditional distinction between oral and written tasks; (c) their perception of the uselfuness of writing activities performed in the science class. Regard- ing interest in writing, the result did not support this hypothesis, in that the differences between pre- and post-instruction ratings of the “Do-you-like?” questionnaire were not significant for any writing task. Most probably, the children’s interest focused mainly on the different experiences in the science class, and therefore writing became a subsidiary activity. This competitive effect of interest is an aspect which should be examined in greater depth.

Regarding the oral-written distinction, a change in the children’s categori- zation of science activities was apparent in their ratings of “To reason and reflect on a phenomenon”, “To reason and reflect on new things you are learning” and “To express what you are not able to understand”. Only the experimental group subjects perceived these three activities as more “written” at the end of the instructional intervention. Making children view writing as a way of reflecting and expressing doubts is certainly an interesting result. One wonders how long this effect may last, and what conditions of science instruction and teachers’ attitudes toward writing strengthen it.

Lastly, the children’s perception of the usefulness of several writing tasks involved in the science experience changed in the expected direction. More children in the experimental group perceived them as useful for learning to write texts at the end of the instructional intervention than at the beginning.

In sum, giving writing in the science class a more important role seems to affect more the ways in which children view this activity – or, at least, some functions of it – while the effects on their interest in writing are lim- ited. Making writing a meaningful activity seems to be easier than making it an attractive one. This study has shown that it is possible to reach the first objective, but more research is needed to show how to reach the second.

Implications

The study contributes to the field of research on the effects of writing on scientific learning in elementary school when writing is used to assist a knowledge construction process requiring conceptual change. The study also

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contributes to the opening of a new line of research to investigate the inter- dependence between writing and learning in a domain. Further research on different types of writing supporting knowledge restructuring and the influ- ence of writing itself on the conceptualization of the writing functions and on attitudes toward writing in the service of learning is needed.

From an educational point of view the study indicates that writing can be successfully introduced in the science class for knowledge construction and reconstruction processes. When it is not (or not only) used as a tool for dis- playing taught knowledge at different levels of complexity but rather as a tool to make sense of new concepts, that is, as a meaningful instrument to be used within a meaningful activity, it contributes to facilitating students’ conceptual understanding and leads them to perceive writing itself as a more useful and effective activity. In other words, representation of the examined phenomena as well as representation of the writing activity may change. When students write to learn and not to reproduce what teachers want them to write, they can think in their own language, with the opportunity to reason and reflect on their own representations. Such reasoning and reflection processes contribute to creating or refining their metaconceptual awareness, crucial to knowledge development. In that respect learning by conceptual change which deeply involves students in higher-order thinking processes represents a particularly suitable experience for the need of using writing meaningfully, perceiving and evaluating it as a powerful activity.

Acknowledgements

We wish to thank the class teachers, Maria Luisa Sartori and Daniela Anselmi, for their great interest and precious cooperation in this study. Moreover, special thanks to all the children.

Note

1. The children’s sentences in group discussions and written texts were translated while trying to maintain the same “tone” as in the original Italian version.

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