A BALANCING ACT: DEVELOPING A DISCOURSE COMMUNITY IN A MATHEMATICS CLASSROOM
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MIRIAM GAMORAN SHERIN A BALANCING ACT: DEVELOPING A DISCOURSE COMMUNITY IN A MATHEMATICS CLASSROOM ABSTRACT. This article examines the pedagogical tensions involved in trying to use students’ ideas as the basis for class discussion while also ensuring that discussion is productive mathematically. The data for this study of the teaching of one middle-school teacher come from observations and videotapes of instruction across a school year as well as interviews with the participating teacher. Specifically, the article describes the teacher’s attempts to support a student-centered process of mathematical discourse and, at the same time, facilitate discussions of significant mathematical content. This tension in teaching was not easily resolved; throughout the school year the teacher shifted his emphasis between maintaining the process and the content of the classroom discourse. Neverthe- less, at times, the teacher balanced these competing goals by using a “filtering approach” to classroom discourse. First multiple ideas are solicited from students to facilitate the process of student-centered mathematical discourse. Students are encouraged to elaborate their thinking, and to compare and evaluate their ideas with those that have already been suggested. Then, to bring the content to the fore, the teacher filters the ideas, focusing students’ attention on a subset of the mathematical ideas that have been raised. Finally, the teacher encourages student-centered discourse about these ideas, thus maintaining a balance between process and content. KEY WORDS: class discussion, discourse community, student-centered discourse, teacher cognition, teacher’s role in discussion A central goal of mathematics reform is for teachers to develop classroom learning environments that support doing and talking about mathematics (National Council of Teachers of Mathematics [NCTM], 1991, 2000). However, creating and maintaining these environments is a complex endeavor for teachers. In particular, two key tensions are apparent. On the one hand, teachers are expected to encourage students to share their ideas and to use these ideas as the basis for discussion. At the same time, teachers are supposed to ensure that these discussions are mathematically productive. The tension comes in trying to find a balance between having a classroom environment that is open to student ideas and one whose purpose is to learn specific mathematical content. These tensions are explored through an investigation of one middle- school teacher’s attempts to implement mathematics education reform. The teacher, David Louis, worked hard to establish and then maintain a discourse community in his mathematics classroom. In doing so, he Journal of Mathematics Teacher Education 5: 205–233, 2002. © 2002 Kluwer Academic Publishers. Printed in the Netherlands.
206 MIRIAM GAMORAN SHERIN struggled to facilitate class discussions in which student ideas were at the center and in which mathematics was discussed in a deep and meaningful way. David explained this dilemma in a journal in which he reflected on his teaching: Today I was forced to consider an interesting issue. The issue is, ‘Do I sacrifice some . . . content in order to foster discussions during class?’ . . . There were several different places today where discussion arose . . . I should have expected that considering I’m trying to set a culture of expressing one’s ideas, but it caught me by surprise a little. At first I tried to press on [to the content he had planned to cover], but students still had [new] ideas. In fact at one point, their ideas [about the content] were quite different than mine . . . [and] when I wanted to move on, they didn’t. (Louis, 1997a, p. 10) Unable to resolve this tension, David moved back and forth in his emphasis on student ideas and on mathematics learning – sometimes striking an excellent balance, and sometimes finding his efforts less successful. The purpose of this article is to characterize how the tension played out in David’s classroom by contrasting the teacher’s focus on the process of mathematical discourse with his focus on the content of mathematical discourse. In brief, the process of mathematical discourse refers to the way that the teacher and students participate in class discussions. This involves how questions and comments are elicited and offered, and through what means the class comes to consensus. In contrast, the content of mathe- matical discourse refers to the mathematical substance of the comments, questions, and responses that arise. This research advances both our theoretical and practical understand- ings of the nature of the teacher’s role in a discourse community. Prior research on teacher cognition has explored the process through which teachers learn to elicit and to monitor student ideas. This article extends such work by examining the tensions involved in this process, and the manner in which teachers manage competing goals. The research described here can also provide teachers and teacher educators with one vision of a discourse community, and with a model for interpreting class discussions and the teacher’s role in such discourse. BUILDING A DISCOURSE COMMUNITY When researchers speak of classroom discourse, or discourse more gener- ally, they are referring to the processes through which groups of individuals communicate (Cazden, 1986; Pimm, 1996). Analyses of discourse decom- pose these processes and underlying structures in different ways. Some researchers attempt to enumerate norms that define aspects of classroom discourse. For instance, norms can govern who can speak and when
A BALANCING ACT: DEVELOPING A DISCOURSE COMMUNITY 207 (Mehan, 1979; Sinclair & Coulthard, 1975). Other researchers look to identify discursive strategies used to support instruction. One example is the work of O’Connor and Michaels (1996), who describe “revoicing” as a technique used by teachers to restate a student’s idea for the class. In still another approach, researchers examine the meaning of particular words and phrases in the context of instruction (Lampert, 1986; Lemke, 1990; Pimm, 1987). Recently, mathematics educators and researchers have placed increas- ing emphasis on fostering classroom discourse that has certain properties (Elliott & Kenney, 1996; NCTM, 1989, 2000). Specifically, students are expected to state and explain their ideas and to respond to the ideas of their classmates. Teachers are asked to facilitate these conversations and to elicit students’ ideas. In this article, classroom environments where such discourse flourishes, are referred to as a discourse community. Further- more, the use of the term mathematical discourse community emphasizes that this communication concerns mathematics in particular. To examine the development of a mathematical discourse community, two related perspectives are examined. The first perspective examines what a mathematical discourse community might look like and evidence that such a community can exist. A second viewpoint considers the teacher’s role in developing a discourse community and the teacher learning that is often required as part of this process. Together, these lenses serve to frame the current study. Visions of a Mathematical Discourse Community Recent research demonstrates that a discourse community can exist in the mathematics classroom. For example, Ball (1993) and Lampert (1990) share vignettes from their own classrooms in which students defend and argue for mathematical ideas. In these examples, students build on the thinking of their peers and the class works to come to consensus on the meaning of important mathematical ideas. Models such as these are crit- ical if we want to help teachers and researchers have a vision of what a discourse community might look like in practice. Additional research seeks to characterize the key components of a discourse community. For example, in looking at how such a community develops, Yackel and Cobb (1996) describe the importance of classroom norms. In particular, they argue for the existence of sociomathematical norms, norms that are specific to participating in discussions of mathe- matics. Thus, while norms for justification and explanation might apply to discourse in any subject matter, they argue that “what counts as an accept- able mathematical explanation and justification is a sociomathematical
208 MIRIAM GAMORAN SHERIN norm” (p. 461). In their view, then, becoming a member of a mathematical discourse community involves learning to talk about mathematics in ways that are mathematically productive. The Teacher’s Role in a Discourse Community Considerable evidence shows that moving from teacher-directed classrooms to more student-centered classrooms places complex demands on teachers (Fennema & Nelson, 1997). First, teachers have a very different role to play in student-centered classrooms than they do in tradi- tional classrooms. In the past, teachers often relied on presenting facts and procedures for students. Today, however, teachers are encouraged to move away from this format of instruction and “telling” is seen as only one of several ways in which teachers can communicate and interact with students about mathematics (Chazan & Ball, 1999). As a result of this shift, teachers need to develop a new sense of what it means to teach mathematics, and of what it means to be an effective and successful mathematics teacher (Smith, 1996). Second, leading a discourse community requires that teachers develop new understandings of content and pedagogy. For example, in studying changes in her own mathematics teaching, Heaton (2000) found that it was relatively easy for her to get students talking and sharing their ideas about mathematics. However, it was quite another matter to understand, from the teacher’s point of view, what to do with those ideas – where to go next, when to pursue an unexpected digression, and when to head off a poten- tial misconception. Heaton claims that she needed new understandings of the mathematics that she was teaching in order to facilitate the discourse effectively. Despite these obstacles, developing a discourse community in one’s classroom can be a powerful form of professional development. Specific- ally, in a discourse community, it is not just the students who learn, but the teacher who learns as well (e.g., Fennema et al., 1996; Hufferd- Ackles, 1999; Schifter, 1998). And the fact that students are sharing and explaining their ideas seems to be a key factor in this learning. For example, previous research demonstrates that novel student ideas prompted teachers to rethink their understandings of mathematics and the pedagogical strategies that they use in teaching such ideas (Sherin, 1996). Because of the critical role that teachers play in the implementation of mathematics education reform, exploring ways to support teacher learning is of great importance to the mathematics education community.
A BALANCING ACT: DEVELOPING A DISCOURSE COMMUNITY 209 Supporting the Process and Content of Classroom Discourse Before proceeding to a discussion of the research design, it is necessary to elaborate on the tension that is the focus of this article – the diffi- culty that teachers face in trying to use students’ ideas as the basis for discussion while also ensuring that discussion is productive mathematic- ally. This challenge can be characterized as a tension between supporting the process of mathematical discourse on the one hand, and the content of mathematical discourse on the other hand. The term process refers to how the teacher and the students interact in discussions – who talks to whom, when, and in what ways. An important component of the process of discourse involves the expectations for participation. For example, are students expected to share their ideas with their classmates? Is the norm that all comments are to be directed to the teacher or to one’s classmates? These questions concern the process of the classroom discourse. The content of the discourse, in contrast, refers to the mathematical substance of the ideas raised, to the depth and the complexity of these ideas in terms of the mathematical concepts under consideration. Further- more, the content of the discourse concerns how closely the ideas that are raised in discussion are aligned with the teacher’s curricular goals and with mathematics as it is understood by the mathematical community that exists beyond the boundaries of the classroom. A number of researchers discuss this tension (Ball, 1996; Jaworski, 1994; Nathan, Knuth Elliott, 1998; Schifter, 1998; Silver & M. S. Smith, 1996; Wood, Cobb & Yackel, 1991), and some make similar distinctions in terminology. For example, Wood (1997) discusses the form and the content of classroom discourse, where form refers to “knowing how to talk,” and content refers to “knowing what to say” (p. 170). Similarly, Williams and Baxter (1996) describe two types of scaffolding that teachers provide for classroom discourse. First, teachers offer social scaffolding that helps to establish and support classroom norms for how students should talk about mathematics. Second, teachers provide analytic scaffolding for structuring how and what mathematical ideas are discussed in class. Both Wood’s form and Williams and Baxter’s social scaffolding are similar to what is defined above as the process of discourse. Furthermore, Wood’s content and William and Baxter’s analytic scaffolding are related to what this research considers the content of discourse. In discussing the tension between supporting the process and the content of classroom discourse, some researchers suggest that teachers manage this tension by first turning their attention to the discourse process, and later, once classroom norms have been established, turning to issues of the content of the discourse (Rittenhouse, 1998; Silver & Smith, 1996;
210 MIRIAM GAMORAN SHERIN Wood, 1999; Wood, Cobb & Yackel, 1991). This research illustrates a somewhat different situation that occurred with David Louis. Though he did lay a foundation of process in the first few weeks and then moved onto to content issues, maintaining the integrity of both the process and the content of the mathematical discourse was a continuing struggle. Throughout the year, David moved back and forth in his emphases, always struggling to balance what proved to be competing goals. The purpose of this article is to characterize this struggle and to explain how and why David ended up shifting his focus between the process and content of discourse in his classroom. CONTEXT AND RESULTS OF LARGER STUDY This research took place in the context of the Fostering a community of teachers as learners project (FCTL) (L. Shulman & J. Shulman, 1994). The central goal of the FCTL project was to examine how middle and high-school teachers from different subject areas might implement the pedagogical reform outlined by Brown and Campione (1992, 1996) in their Community of Learners (COL) research. In addition, the researchers explored the design of professional development and teacher education activities intended to support teachers’ efforts to implement the COL pedagogy. The Teacher The teacher, David Louis, taught middle-school mathematics in an upper- middle class suburb of the San Franciso Bay Area. During the 1995– 96 school year, he explored how specific COL participant structures and principles might apply to a mathematics classroom. To do so, the teacher designed and tested curriculum units that incorporated many of the COL participant structures. For example, groups of students worked together to become experts in a specific area and were then organized into “jigsaw groups” comprised of experts in each of the different areas. Context for the Study In the summer of 1996, two researchers from the FCTL project (Edith Prentice Mendez and the author) met with David to discuss his experience thus far with the COL pedagogy. David explained that despite imple- menting COL units, he did not believe that the COL principles had come alive in his classroom and he had yet to feel that he had successfully developed a community. Furthermore, David had come to believe that encouraging students to talk about their ideas was the critical element
A BALANCING ACT: DEVELOPING A DISCOURSE COMMUNITY 211 in developing community in the mathematics classroom. Thus, for the coming year, he planned to focus on developing a “mathematical discourse community” rather than adhering strictly to what he thought was the struc- ture of typical COL units. He imagined a classroom in which students were “enthusiastic about sharing their ideas with their classmates” and in which “students would comment on and critique each other’s ideas” (Louis, 1997b, p. 4). Data Collection During the following school year, 1996–97, we observed and videotaped in the teacher’s classroom, choosing one eighth-grade class as the focus of the data collection. This class met four days a week. From September to December, an average of three of the four classes were observed. And from January through June, two classes a week were generally observed. In all, 78 classes were observed and videotaped throughout the school year. In order to capture much of the discourse that took place in the classroom, we used multiple microphones and an audio mixer. The teacher wore a wireless lapel microphone, and two additional microphones were placed around the room on students’ tables. The sound was then fed through an audio mixer to the video camera. In addition, we made copies of all assignments given in class and of all the overhead transparencies that were used. Field notes also were collected for the days observed. For all lessons, a lesson-structure summary was created during the observation. This summary listed the various activities that comprised the lesson on that day, gave brief descriptions of each and the times at which each activity began. In addition, for over 60% of the observations, more detailed notes were taken during class. One focus of these notes was to track the mathema- tical ideas that were discussed in class and to record how these ideas were represented and by whom. The notes often contained snippets of transcripts from class discussions. Similar notes were made for the rest of the lessons using the videotaped data. In addition to the classroom data, the teacher kept a written journal in which he reflected on his teaching approximately three times a week from September to December, and twice a month after that. David, Edie, and I also met once a week to discuss what was happening in David’s class and to watch video excerpts from the class. Furthermore, the teacher was inter- viewed four times across the year. In these interviews, David discussed his goals for the coming year, his impressions of the discourse that existed in his classroom, and his perspective on what he and his students were learning. The meetings and interviews were audiotaped and transcribed.
212 MIRIAM GAMORAN SHERIN Data Analysis The research described in this article seeks to understand teaching by looking closely at classroom interactions across one school year. In general, the research reported is qualitative in nature, based on analysis of videotape data and interviews with the teacher. Furthermore, the teacher whose classroom is the focus of this study, David Louis, was a collaborator throughout the project. Analysis for this study focuses on class discussions. First, using video- tapes and observation notes, those lessons in which a class discussion was one of the primary activities of the day were identified. This included a total of 68 lessons across the school year1 . Preliminary analysis then involved coding these lessons on a coarse scale (high vs. low) for the extent to which David focused on the process and the content of the classroom discourse. Discussions in which his focus was rated high on process were those in which David consistently elicited students’ ideas and asked students to comment on each other’s ideas. In contrast, discussions rated low on process were mainly teacher-centered with little room for students to contribute their ideas. Discussions in which David’s focus was rated high on content were those in which his comments were intended to move the discussion along mathematically. For example, David might compare and evaluate the mathematical substance of ideas that arose or ask the students to do so, or he might direct their attention to a relevant mathematical issue. Discussions rated low on content were those in which David allowed extended discussion of non-mathematical ideas or ideas which were only superficially mathematical. Initially, one researcher coded the entire data set in this manner. A second researcher then reviewed the coding of each lesson. Agreement between the two researchers for each lesson was 91% and above. Cases of disagreement were reviewed together until the researchers reached consensus. Table 1 displays the results of this coding. TABLE I Distribution Across Lessons of David’s Focus on Process and Content Low Process High Process Low Content 28% (19 lessons) High Content 15% (10 lessons) 57% (39 lessons)
A BALANCING ACT: DEVELOPING A DISCOURSE COMMUNITY 213 A number of questions arose based on this preliminary analysis. First, what happened in those lessons in which David apparently focused on both process and content? Was he able to use the students’ ideas to discuss the key mathematical concepts in the lesson? And what affected whether and how this was achieved? In addition, why was it that at some times David chose to focus on either process or content, but not on both? And how did those lessons play out in class? Investigating these questions formed the research study that is reported in this article. STUDYING THE TENSION BETWEEN PROCESS AND CONTENT In order to investigate these issues, a subset of 20 lessons from across the school year were selected for more detailed analysis. In general, one lesson was selected every other week from September through May. Because of various school holidays that occurred throughout the year, the 20 lessons were comprised of two lessons per month from September through May, with a third lesson included from the months of September and February. No lessons were selected from the month of June because school ended during the first week of that month. Class discussions from these 20 lessons were transcribed and a fine- grained analysis of video (Schoenfeld, Smith & Arcavi, 1993) was then used to analyze the teacher’s role in these discussions. In particular, based on prior research on the role of discourse in the mathematics class, specific areas of discussion were identified to be the focus of the analysis (Ball, 1991; Brown & Campione, 1994; Mendez, 1998; NCTM, 1991; Silver, 1996). These areas included the questions raised by the teacher, the teacher’s responses to students’ questions, the mathematical content intro- duced by the students, and the mathematical content introduced during discussion by the teacher. In addition, analysis examined the different mathematical representations used during discussion. The results of this analysis are described in the next section. RESULTS The tension between process and content in David’s classroom played out at two time scales: (a) at a macro-level across the year, and (b) at a micro- level, within class discussion in individual lessons. First at the macro-level, David’s efforts to balance process and content across the school year are discussed. These results draw from the coarse ratings of all 68 lessons as
214 MIRIAM GAMORAN SHERIN being high or low on process and content as well as from analysis of the 20 lessons selected for more detailed study. Following this, David’s efforts to balance process and content within particular class discussions, the micro- level, are examined. The focus here is exclusively on the analysis of the 20 selected lessons. Process and Content at the Macro Level Across the school year, David shifted his efforts between supporting the process and the content of the discourse community that he desired (Figure 1). Initially, David’s interest was in process; the first seven lessons of the year were coded as high on process and low on content. Two of those lessons were the focus of detailed analysis. From the observer’s perspective they reveal that during this time, David’s goal was to establish the struc- ture for class discussion. In general, he did this by brainstorming with the class about appropriate roles for the students during class discussions and by experimenting with these roles in the context of non-mathematical activities. Thus, students were explaining and comparing ideas, however these ideas were not mathematical in nature. For example, on the first day of class, groups of students worked together to make shapes with a loop of yarn. The class then came together to discuss the activity and David encouraged the students to comment on working as a group rather than on the different shapes that students had been able to make and why2 : D. Louis: How did it feel to [work in groups] today? Jason: Fine. D. Louis: Expand. Jason: It was easier because when we had a problem, it was easier to work through if you had someone to talk to about it. D. Louis: What do other people think about what Jason said? Do you agree or disagree? Ben: I agree. Julie: I agree too. Without group members you couldn’t hold the corners [of the yarn]. In writing about this lesson in his journal, David was explicit that his goals for the day were to “debrief with attention to questioning techniques,” and to “comment on discussion skills.” Furthermore, he was not concerned that “we didn’t discuss too much mathematics [today]” (Louis, 1997a, p.2). Instead, David had chosen specifically for the start of the school year, to focus on establishing the process of discourse in his classroom.
A BALANCING ACT: DEVELOPING A DISCOURSE COMMUNITY 215 Figure 1. A sketch of David’s emphasis on process and content across the year. After a few weeks, David was satisfied that the norms for discourse he had envisioned were established and he was ready to add content to this process. In an interview he explained: [T]he students learned the protocol for talking to each other . . . and listening to ideas, and they learned expectations for giving ideas . . . The basic skeleton of norms are there. Now they [need to] move past that and talk much more about [mathematics], to use the protocol that I’ve tried to establish to learn math. David began to prompt the students to talk about mathematics and the students responded accordingly. For example, in the following lesson, students worked in groups to determine a method for estimating the number of dots placed randomly in a 9 × 14 cm rectangle (Lappan, Fey, Fitzgerald, Friel & Phillips, 1997). Several students then explained their group’s method to the class: Julie: We divided [it] up by one centimeter by one centimeter . . . and then we’d have 126 little squares. So we counted [the dots in one of] the little squares and there’d be about 17 little dots in there. So then we multiplied 17 by 126. D. Louis: Okay. What do people think about this group’s method? Robert: I think it’s a good idea but bigger squares would have been more accurate. D. Louis: Why do you say that? Robert: Because . . . there may be a bunch of dots packed into a small area. In just that particular area. Or, there might be not a lot of dots. Amy: I agree . . . because there are not the same amount of dots in the same place. D. Louis: And why would that make a difference?
216 MIRIAM GAMORAN SHERIN As seen in the above excerpt, in discussing the activity as a class, David focused on the mathematics of the problem. He asked students to comment on and to compare the different groups’ methods. Furthermore, he encour- aged Amy to explain why the two different methods would produce different results. Achieving balance. A balance had now been achieved with David focusing on both the process and the content of the classroom discourse. Students were asked to share their ideas and to comment on the ideas of others, and they were expected to do so in the context of the mathematics of the given activity. This balance lasted at the macro level for several months.3 In fact, during the months of October, November, and December, over 85% of the lessons were rated as high on both process and content. David was pleased with the level of discourse that the class had achieved. He wrote: There are several interesting things happening here. First, the [discourse] norms are hard at work. Students are building on each other’s knowledge and work. . . The second . . . is the mathematics. I never would have expected to discuss [the mathematics] in such detail and depth. (Louis, 1997b, p. 21) Shifts from balance to process or content. Mid-year however, the balance shifted. In January and February, over 50% of the 68 total lessons were rated high on process but low on content, similar to the beginning of the school year. This shift appears due to the fact that David had become concerned with the level of justification that students offered in support of their ideas and methods. In writing about his goals for the second half of the school year, David stated that he wanted to improve the classroom discourse by “focusing with students on what counts as justification for a mathematical idea” (Louis, 1997b, p. 5). In discussing this goal in an interview, David explained that he wondered if he had made it clear to the students that “you shouldn’t let things by without a justification . . . and [that] it’s the class’ responsibility to judge this.” He was also concerned at times that “students would agree with each other, but without expressing a different viewpoint than the one first given.” For example, a student would respond by saying, “I agree because of the same reasons that Amy gave.” With this in mind, David once again turned his focus to process and encouraged students to take on new roles in the structure of class discussions. In particular, students were expected to contribute to class discussions not only by sharing their ideas, but also by providing the reasoning behind those ideas and by judging whether their classmates had given sufficient justification for an idea. For example, David explic- itly discussed with students whether the statement, “I agree because that’s what I got,” is a “good” mathematical argument. Other prompts
A BALANCING ACT: DEVELOPING A DISCOURSE COMMUNITY 217 that David used included “How could you verify that Jin’s conclusion is correct?” and “Does that make you more convinced?” In a sense, David was attempting to renegotiate the classroom norms for participating in discussion to include a sociomathematical norm for justification (Yackel & Cobb, 1996). However, David’s emphasis on justification occurred partly at the expense of the mathematical content of the lessons. He worked hard to help students justify their ideas and was less concerned with the direc- tion that the discourse took in terms of the mathematical concepts under discussion. Thus, during this time, his main emphasis was on process, with less attention given to content. A final shift occurred late in the year when David began to teach a unit on algebra. In contrast to lessons earlier in the year, during the algebra unit over 85% of the coded lessons were rated low on process and high on content. At the end of the year, David chose to emphasize the content that he wished students to learn. Furthermore, David set aside the pattern of discourse that had developed in his class, and relied on more teacher-directed instructional techniques to introduce the class to algeb- raic methods. For example, David wanted the students to create a table showing how the price of a pizza depended on the base price plus the cost per topping. Rather than asking students how they might represent this information, David gave the class explicit instructions for making a T-table and filling in the columns. David himself recognized this shift in pedagogical style and wrote about it in his journal: [Today’s] lesson was quite different than what I was used to . . . What happened today was much more directed instruction than usually exists in my classroom . . . I was telling the students what I wanted them to know about [algebra] . . . I just showed them what to do and why to do it. I didn’t provide a forum for discussion about student ideas or check for understanding via discourse. (Louis, 1997a, p. 39) David’s reasons for focusing on content at this point in the year were two- fold. First, David was influenced by his beliefs about the nature of algebra. David explained to his class at the beginning of the algebra unit that he believed algebra was a highly structured domain and that learning algebra required a structured approach. Thus David believed that he needed to sacrifice the open-endedness of the discourse in order to help students learn a set of predetermined algebraic procedures. In his journal he claimed that the shift in his pedagogical style was due to “the [math] that I wanted to discuss today” (Louis, 1997a, p. 39). Second, David taught in a community that was highly political and was in the midst of a controversy concerning mathematics instruction. While there were many proponents of mathe- matics reform in this community, support came mainly for reform at the elementary and middle school levels. At the same time, a very vocal group
218 MIRIAM GAMORAN SHERIN of parents and teachers at the high school level argued for more emphasis on skill and computation in order to help prepare students for high school and college mathematics. As a result of this controversy, David was partic- ularly sensitive about his teaching of algebra – a topic that is typically taught at the high school level, or only in an honors class at the eighth grade. He wrote, “I could not help but think, what if a parent were to view this videotape?” (Louis, 1997c, p. 3). Summary. This analysis shows that the tension between process and content was not something that David easily resolved as the school year progressed. It was not the case, as one might have imagined, that David began the year struggling to find a balance between process and content, but once a comfortable balance was reached, it was maintained for the rest of the school year. On the contrary, Figure 1 illustrates that this dilemma was ongoing throughout the year as David continued to shift his emphasis between the process and the content of classroom discourse. Process and Content at the Micro-level Fine-grained analysis of 20 lessons from across the year show that the tension between process and content existed not only at the macro level as described above, but also arose within individual class discussions. Specifically, in the context of a single discussion, David shifted his emphasis between the process and the content of the discourse. Further- more, it appears that moving back and forth in his emphasis at times helped David to facilitate meaningful discussions about mathematics in which students’ ideas were a key component of the discourse. How did this occur? Prior to the beginning of the school year, David identified three ques- tions that he planned to use to guide his comments during class discussions. Based in part on his viewing of a videotape of Deborah Ball teaching mathematics to third grade students (Ball, 1989), David planned to ask the following questions: 1) “What do people think about this idea?” 2) “Why?” and 3) “What do other folks think about that?” David hoped that using these questions repeatedly would encourage students to share their ideas and to build on each other’s ideas. These questions represented a pattern of discourse that was quite different from traditional classroom discourse in which discussion followed a pattern of IRE – 1) Initiation by the teacher, 2) Reply from the student, followed by 3) an Evaluative comment from the teacher (Mehan, 1979). Instead, David planned to respond to students’ comments with additional questions, either asking the student to elaborate or for other students to comment on the idea.
A BALANCING ACT: DEVELOPING A DISCOURSE COMMUNITY 219 As a result of using these three questions, a structure for class discus- sions emerged. Specifically, many of the class discussions followed a similar format involving three main components: (a) idea generation, (b) comparison and evaluation, and (c) filtering (Figure 2). In the first part of discussion, idea generation, David elicited ideas from students concerning whatever topic was being discussed. He used the three questions extens- ively to facilitate this initial brainstorming of ideas. David would elicit an idea from a student by asking, “What do you think?” After the student responded, David would ask for elaboration: “Why?” or “Can you explain that?” David would then turn to the rest of the class and ask, “What do other people think?” Following this trio of questions, David would cycle back to the first question, “Okay. Other ideas on this?” and the cycle continued. As can be seen from this description, ideas were not only gener- ated, but were also preliminarily elaborated and evaluated by members of the class. At this point in the discussion, David was not particularly worried about taking control over the content that was being raised. Instead, as he explained in an interview, he used the three questions at the beginning of a discussion to “draw out kids’ ideas,” and to give the students a sense of ownership over the discourse. Figure 2. Components of class discussion. Once several ideas had been raised, the class generally shifted into a second phase of discussion: comparison and evaluation. The shift was somewhat subtle. Rather than asking for one new idea and then another new idea, and then another, David’s questions focused more on asking students to consider one idea in light of another, “So, is what you’re saying the same as Tina? What do you think?” Students’ comments also reflected this shift. Students were less likely to introduce new ideas at this stage, and were more likely to state whether they agreed or disagreed with a particular idea that had been suggested. The final structure was filtering. Here the class narrowed the space of consideration and developed a plan to investigate a few ideas in detail. Some ideas that had been raised were highlighted and pursued further, while others were set aside for the moment. This occurred as David focused the class overtly on two or three specific ideas. In addition, David
220 MIRIAM GAMORAN SHERIN introduced new mathematical content intended to help the class sort out the issues under consideration. David’s emphasis here was on content issues. He explained that he would “look for strategic, timely entries into the conversation to push the mathematics to a higher level . . . to tie together, or help make conclusions” (Louis, 1998, p. 5). The term filtering is used to emphasize that any new content raised by the teacher is based on a narrowing of ideas raised already by the students. Other researchers also identify this seeding of ideas as an important component of mathematics instruction. For example, Chazan & Ball (1999), argue that substantive mathematical comments on the part of the teacher can be a valuable cata- lyst for class discussions. Similarly, Wood (1994, 1995, 1997) talks of teachers using a series of “focusing” questions that serve to direct students’ attention to the key elements of a particular solution strategy. Yet after asking these focusing questions, the teacher did not take an active role in discussing the ideas with the class. In contrast, during filtering, David worked with the students to examine the narrow set of ideas that were now under consideration. The three components shown in Figure 2 appeared quite regularly in class discussions. Of the 20 lessons selected for detailed analysis 19 involved idea generation, 16 involved comparison and evaluation, and 18 of the lessons included filtering. Furthermore, 15 of the 20 lessons contained all three structures. Despite the frequency with which these structures appeared, David’s class did not adhere rigidly to a prescribed format for class discussions. On the contrary, class discussions proceeded in a rather fluid manner. Although in general, the class progressed through the three structures in the order presented here, it was not always the case. In particular, a single discussion might involve cycling through these components more than once, or repeating the first two components a number of times before moving to filtering. Furthermore, further idea generation or additional comparison and evaluation of ideas often followed filtering.4 Taken together, the three components can be thought of as a framework that highlights the ways in which different processes were used by the teacher to make progress on content issues. As such, the framework is particularly useful in exploring the tension that David faced in supporting both the process and the content of classroom discourse. In particular, it is possible to consider how control over each of the three processes shifted among the teacher and the students and the affect that this shift had on the mathematics that was discussed.
A BALANCING ACT: DEVELOPING A DISCOURSE COMMUNITY 221 AN EXAMPLE FROM THE CLASSROOM To examine this framework more closely, consider the following example from the classroom. This example comes from a lesson that was coded as high on both process and content. Thus, at the macro level, David was trying to support the process and the content of the mathematical discourse. However, at the micro level, David continued to shift between these two goals throughout the discussion. In doing so, David was able to draw out student ideas and to use these ideas to pursue what he believed to be the mathematical content of the lesson. Far from being an anomaly, this example is representative of many class discussions that took place throughout the school year. In discussions such as these, the claim is that David achieved an effective balance between his goals of supporting student discourse and facilitating the learning of mathematical content. Furthermore, examining David’s use of the discourse structures outlined in the previous section helps to explain why this is the case. Background on the slingshot lesson. The slingshot lesson took place during a unit on functions in the second month of school. The lesson lasted for two and a half class periods. An important goal of the unit was for students to explore the relationship between changing quantities. This lesson followed a format that was similar to several other lessons in the unit. Students would first collect some data, they would then graph the data, and finally they would write an equation to represent the relationship involved. For example, the previous week, the students had measured the changing height of the water level as one, two, and then three cubes were added to a cup of water. To be clear, these students were not in a pre- algebra or algebra class, and the goal of the unit was not the standard y = mx + b material. Instead, the unit was intended to give students experience exploring data, interpreting graphs, and writing simple linear equations. During the slingshot lesson, small groups of students were given an apparatus that resembled a slingshot. The apparatus, which consisted of a rubber band strung between two nails, rested on the floor. Using the rubber band, students were to measure the distance that a small ball made out of tinfoil traveled along the floor after being released from the slingshot (Figure 3). The groups were to begin by pulling the rubber band back one centimeter and letting the ball go. They would then repeat the experiment for two and three centimeters. Students were encouraged to take more than one measurement for each of the three distances, and to average their results. Unlike the cubes in a cup lesson, here David did not expect the class to produce uniform data. While he believed that in an ideal physical world, increasing the stretch of the rubber band by a constant amount would result
222 MIRIAM GAMORAN SHERIN Figure 3. The slingshot apparatus. in a constant increase in the distance the ball traveled, he recognized that the classroom was not an ideal physical world.5 Thus David did not expect the students’ data to exhibit a linear relationship perfectly. He explained that the class “was entering the wide world of a data collection” where “you never know what you’re going to get.” In particular, David believed that it would not be a simple matter for the students to find an equation that corresponded to their data. Fire away: The slingshot lesson in action. On the first day of the slingshot lesson, the students worked in groups to complete their data collection. Following this, David held a brief discussion before the end of the period. During this time, the students raised a number of ques- tions regarding the procedures they had used for collecting their data: “We couldn’t make the ball go straight,” and “Our rubber band broke so we stapled it. Does that matter?” Before handing out the homework, David encouraged the students to begin looking for patterns regarding how far the ball traveled. He asked, “For every centimeter you pull it back, the ball goes how far?” David explained that the class would pick up the discussion on the following day. David began class on the second day of the lesson by reviewing the students’ homework. For homework, the students were asked to complete a worksheet with six questions concerning the slingshot activity. The first two questions, which are listed below, formed the basis for much of the class discussion (Figure 4). This discussion is the focus of analysis. Figure 4. The slingshot homework assignment. The class quickly agreed that, in Patrice’s equation, y corresponded to the distance that the ball traveled and x corresponded to the amount that the rubber band was stretched. Furthermore, it was clear that in Patrice’s
A BALANCING ACT: DEVELOPING A DISCOURSE COMMUNITY 223 case that for every centimeter that you pulled the rubber band back, the ball traveled another 120 centimeters. David then asked, “Was it pretty accurate to say that it’s about 120 centimeters?” In response, students introduced a number of factors that they believed would affect whether or not the ball traveled 120 centimeters. The following interaction is typical of the conversation that took place: D. Louis: What do you think? Jeff: Depends on what floor it is. D. Louis: Okay, depends upon what floor it was. Why do you say that? Jeff: The more, the less, the less friction, the further it goes. D. Louis: Okay, what do other people think? The students recognized that their data did not demonstrate the constant increase suggested by Patrice’s equation. Thus, they suggested other factors as possible reasons for some variation within each group’s data. Additional variables mentioned included human error and the fact that the balls did not always travel in a straight line. After a few minutes, Ben joined the conversation, raising an issue that was somewhat different from the types of comments made up to this point. Ben explained that while the factors that students had named already would account for some of the variation the groups encountered in collecting their data, there might also be another issue in play. Specifically, Ben wondered if the increase in distance might not actually be constant. Another student, Robert, then explained that if this were the case, graphing the data would produce a curve rather than a line. Ben: I also think it depends like on how far you pull it back. D. Louis: What do you mean? Ben: Like if you pull it back to the one centimeter, and you do that like three times, like it might be 120 centimeters. But then the first time that you pull it back it, say the second one, it might be farther than 120 centimeters. It might just keep going at a steady rate, but . . . it might be larger than 120 centimeters apart. D. Louis: Does anyone understand what Ben is saying because I don’t quite exactly understand . . . Robert: I think he means that the graph might not be linear. If you make a graph out of it, it might not go at a constant rate. D. Louis: Is that what you’re saying? Ben: Yeah. D. Louis: What do other people think about that?
224 MIRIAM GAMORAN SHERIN As the conversation continued, Jeff responded in agreement with Ben, “The change between zero cm and one cm will be less than the change between one cm and two cm.” In contrast, Sam argued that the variation was due to human error and was not because the difference in the distance traveled was increasing. At this point, David highlighted these two issues for the class: D. Louis: So I hear people saying two things. One group of people [is] saying that you pull back a certain amount, and then it will go that much farther each cm you pull it back. So each time it goes 120 centimeters farther . . . the same amount farther each time. I hear another group of people saying that possibly, the further you pull it back each time, it goes a little farther. So if you pull it back the first time it goes 120, and you pull it back the second time, or 2 cm back, it might go 140. You pull it 3 centimeters back, it might, well the first was 120, then 140, and then maybe 160. So it goes a little farther each time you pull it back. So what do you guys think about that idea? To respond to David, students began to look at their data to see which pattern fit most accurately. Soon David suggested that the class pursue this issue using the graphing calculator. David introduced the notion of a “scatter plot” as a graph whose values do not make a perfectly straight line. With the students’ help, David entered one group’s data into a graphing calculator that worked with the overhead projector. David selected the scatter plot function so that the data was now displayed in view of the entire class. The students discussed how to visually estimate which one line would most accurately represent the data. In addition, they used the graphing calculator to determine a “line of best fit.” In this way, the class was beginning to deal with different ways to interpret the complex set of data that had been collected. In fact, students began to offer a number of different ideas about why the notion of scatter plot was useful for them, and how they could determine whether one of their own estimates was a line of best fit. Analysis of the slingshot lesson: A filtering process. In this example, David achieves multiple goals. In particular, he achieves a balance between process and content by first allowing a great deal of open-ended discourse, and then by focusing the discussion himself, and thus taking more control of the content. The beginning phase of the discussion is a typical example of idea generation. David uses the three questions to draw out students’ ideas and to keep the conversation moving. The content of the discussion is clearly in the students’ hands at this point, as they are the ones suggesting which factors affect the data.
A BALANCING ACT: DEVELOPING A DISCOURSE COMMUNITY 225 After students raised several ideas concerning why the distance might not consistently be 120 centimeters, there is evidence that the class shifts into the comparison and evaluation structure. In particular, Ben’s comments indicate that he has classified the ideas raised thus far as being about physical factors that affect data collection. In contrast, Ben had a different kind of argument to make. Following Ben’s comment, David encouraged further comparison among the students’ ideas including eval- uation of Ben’s proposal. Thus, in this phase of discussion, the students and David appear to share responsibility for the content of the lesson – yet open-ended discourse is still a prominent feature of the discourse. The beginning of the third phase, filtering, is much more obvious. Here, David shifts his position in the conversation somewhat and brings the students’ attention to two particular ideas. In addition, he seeds the ensuing discussion with the notion of a scatter plot and of finding a line of best fit. For a time then, David has taken control of the content of the conversation, and has narrowed the space of ideas being raised and discussed. Open- ended discourse is not closed off completely, in fact David often asks for student input to explain the ideas he is presenting. However, this part of discussion resembles teacher-directed discourse more than that which occurred earlier. The class then uses this filtering by David to redirect their attention, and return again to idea generation. Specifically, they began to discuss what a “line of best fit” would look like (e.g., “There must be the same number of data points above and below the line.” “Should some data points pass through the line?”) It is important to note that considering how to interpret a scatter plot and how to determine the features of a line of best fit, consti- tute significant mathematical content for these students. In the past, they had explored data intended to represent linear functions more precisely – the difference between data values was often consistently the same. Here the students were dealing with a very different set of data and they needed a new set of mathematical tools to do so. The combination of the graphing calculator with the notion, not of a line that fit perfectly, but rather of a line of best fit, had the potential to help them explore these issues productively. Examining the flow of ideas in the class, a pattern is evident. First, in terms of the process of mathematical discourse, many ideas are encouraged early on, a few are chosen for more focused attention, and then the class returns to soliciting many ideas. This is a view of the process of mathe- matical discourse because it describes how and when ideas are solicited. Furthermore, this particular process involves a great deal of open-ended discourse in which students are encouraged to have control of the ideas being raised.
226 MIRIAM GAMORAN SHERIN Figure 5. A representation of the process of the classroom discourse. Second, this approach serves a very different purpose for the content of mathematical discourse. Each time that the teacher narrows the scope of ideas that are considered during filtering, he takes control of some of the mathematics that is discussed. And even though many ideas are then gener- ated about this filtered topic, the mathematical content has nevertheless been redirected and narrowed. As this cycle is repeated, the mathematical content of the lesson moves from a broad arena to one that is more focused. The initial question or topic that the teacher raises is certainly an important factor in determining the direction of the content of the discussion. Yet in addition, the filtering process allows the teacher continually to refocus the content of discussion in areas that he or she feels are mathematically significant and that will be productive for the class to pursue (Figure 6). Figure 6. A representation of the space of mathematical content.
A BALANCING ACT: DEVELOPING A DISCOURSE COMMUNITY 227 Taken together, these two perspectives demonstrate how David was able to balance the process and content of mathematical discourse in conversa- tions such as the one discussed here. Furthermore, this example illustrates that this balance was achieved in part because David shifted his emphasis between process and content in the context of the discussion. Thus, rather than hindering his goals, at times, the ongoing tension between process and content was an important factor in enabling David to facilitate classroom discourse successfully. DISCUSSION AND IMPLICATIONS Teaching with open-ended discourse poses a problem for the learning of content. On the one hand, students are expected to learn specific content, but on the other hand, students’ ideas are supposed to direct the discus- sion. How do teachers respond to the need to support both the process and the content of classroom discourse? Under what circumstances are they able to manage both of these goals simultaneously? Based on the analysis presented in this article, two issues are proposed as being at the core of teachers’ efforts to meet these competing demands. For each issue, both theoretical implications and considerations for teacher education are discussed. New Structures for Classroom Discourse First, the teacher does find ways to structure class discussion in order to support both the process and the content of classroom discourse. Specific- ally, a filtering approach involving a combination of three discourse processes is used to make progress on content issues. In this approach, multiple ideas are solicited from the students in the initial phase. Students are encouraged to elaborate their thinking, and then to compare and eval- uate their ideas with those that have already been suggested. The filtering part of the discussion comes next, as the teacher focuses the students’ attention on a subset of the ideas that have been raised. In addition, the teacher may introduce a new mathematical idea or approach that the class can use to consider the focused content. This focusing on the part of the teacher is then followed by additional idea generation on the part of the students. A single class discussion may involve several cycles of this pattern. This filtering approach can serve both process and content goals. In terms of process, the students have a great deal of opportunity to share their thinking and the teacher’s “filtering of ideas” is based on the ideas
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